ANN. MISSOURI BOT. GARD. 91: 159?185. 2004.
GEOGRAPHICAL
DIVERSIFICATION OF
TRIBES EPILOBIEAE,
GONGYLOCARPEAE, AND
ONAGREAE (ONAGRACEAE)
IN NORTH AMERICA, BASED
ON PARSIMONY ANALYSIS
OF ENDEMICITY AND TRACK
COMPATIBILITY ANALYSIS1
Liliana Katinas,2 Jorge V. Crisci,2 Warren
L. Wagner,3 and Peter C. Hoch4
ABSTRACT
Tribes Epilobieae, Gongylocarpeae, and Onagreae, a monophyletic branch in the family Onagraceae, comprise genera
endemic to or having their major basal radiation in the Madrean Floristic Region of southwestern North America.
Parsimony analysis of endemicity (PAE) and panbiogeography (track compatibility analysis) were performed in order to
seek an historical explanation for the patterns of high diversity and endemicity for the group in this region. Twenty-
one areas of endemism are delimited, based on previous biogeographic schemes and presence of endemic plant and
animal taxa. Based on distributional data on 173 species, a strict consensus PAE cladogram shows four main groups
of areas: northern North America, the central Mexican areas, western North America, and eastern North America. Track
compatibility analysis resulted in two strongly supported generalized tracks: one includes eastern North America, and
the other western North America. PAE and panbiogeographical analyses of the distributional patterns of these taxa
suggest a close relationship of eastern and western North America, with both areas more related to the Neotropics than
to the Palearctic, and a rather weak association between northern North America and Asia. The discovery of two tracks
in eastern and western North America for Epilobieae, Gongylocarpeae, and Onagreae reveal little relationship of North
America with Asia or other continents. These tribes display a distinct but contemporaneous biogeographical history
that differs from those of the Holarctic. These eastern and western tracks show that ancestral biotas existed on each
side of North America, with the species of each track sharing a common history.
Key words: biogeography, endemicity, Madrean, Onagraceae, panbiogeography.
Recent developments in biogeography have
highlighted the importance of the spatial distribu-
tion of organisms as a direct subject of analysis
(Craw et al., 1999; Crisci, 2001; Crisci et al., 2000,
2003). The Onagraceae, a moderate-sized, sharply
defined, homogeneous family, have been intensively
studied (Raven, 1979, 1988; Hoch et al., 1993;
Levin et al., 2003, 2004) and thus constitute an
excellent group within which to develop such bio-
geographic studies.
1 The authors thank the Consejo Nacional de Investigaciones Cient??ficas y Te?cnicas (CONICET, Argentina), Missouri
Botanical Garden, and Smithsonian Institution for generous support of this project; primary support for this project
came from the Smithsonian Institution Andrew W. Mellon Fellowships in Structure and Evolution of Terrestrial Eco-
systems program. We also thank Peter Raven for setting the stage for this analysis through his long study of the
Onagraceae, and for his encouragement of this project. We thank Alice Tangerini for preparing the excellent graphics
in the figures, Denise Mix for her great help in preparation of the figures and for logistic support for the project, and
Tom Hollowell for assistance with the ArcMap base map for the figures. We also thank Matt Lavin, Jun Wen, and an
anonymous reviewer for useful comments.
2 Divisio?n Plantas Vasculares, Museo de La Plata, Paseo del Bosque s/n, 1900 La Plata, Argentina. katinas@
museo.fcnym.unlp.edu.ar, jcrisci@netverk.com.ar.
3 Department of Systematic Biology, Botany, MRC 166, Smithsonian Institution, P.O. Box 37012, Washington, D.C.
20013-7012, U.S.A. wagner.warren@nmnh.si.edu.
4 Missouri Botanical Garden, P.O. Box 299, St. Louis, Missouri 63166-0299, U.S.A. peter.hoch@mobot.org.
The family Onagraceae includes six monogeneric
tribes?Circaeeae, Fuchsieae, Gongylocarpeae,
Hauyeae, Jussiaeeae, and Lopezieae?and two
larger, more diverse tribes, Epilobieae and Ona-
greae (Raven, 1979; Hoch et al., 1993; Levin et al.,
2003). Tribes Epilobieae, Gongylocarpeae, and On-
agreae, which form a monophyletic branch in the
family (Levin et al., 2003), are biogeographically
distinct because almost all 11 genera in these tribes
are endemic to or have had their major basal ra-
160 Annals of the
Missouri Botanical Garden
diation in western North America. A primary con-
centration of genera exists in the Madrean Floristic
Region (Takhtajan, 1986), comprising the south-
western United States and northern Mexico. This is
an area of great geological and climatological com-
plexity with a rich and highly characteristic biota
(Axelrod, 1958; Axelrod & Raven, 1985; Takhta-
jan, 1986).
Gongylocarpus, until recently included in the
Onagreae, and Xylonagra (Onagreae) are endemic
to western North America, and Camissonia, Clark-
ia, and Gayophytum (all Onagreae) have the great
majority of their taxa in the region, especially in
the California Floristic Province (Raven & Axelrod,
1978); each of the latter three genera also has one
or two species in temperate South America. The
remaining genera of Onagreae (Calylophus, Gaura,
Oenothera, Stenosiphon) have centers of diversity
further east in North America, although Gaura ex-
tends into central Mexico and Oenothera into Cen-
tral and South America. One exception to the pre-
dominantly North American nature of these tribes
is Chamerion (the fireweeds), a genus of Epilobieae
with six of its eight species and one of two sections
endemic in Europe and Asia. Tribe Epilobieae def-
initely has a north temperate origin, with a distri-
bution pattern that suggests a more complex history
of diversification (Raven, 1976; Baum et al., 1994).
All seven sections of Epilobium (including the for-
mer segregate genera Boisduvalia and Zauschneria)
occur in or are restricted to the Madrean Region,
with the large section Epilobium diversified on all
other continents except Antarctica.
In order to seek the historical explanations that
led to the high diversity and endemicity of Epilo-
bieae, Gongylocarpeae, and Onagreae in North
America, we will analyze the patterns of distribu-
tion of species of these tribes native to North Amer-
ica (for a list of species and references, see Table
1). A focus on patterns of distribution requires con-
ceptual and methodological tools that allow com-
parisons to be made in a meaningful and informa-
tive way. Two modern approaches that allow this
kind of analysis are parsimony analysis of ende-
micity and track compatibility analysis (panbi-
ogeography) (Morrone & Crisci, 1990, 1995; Crisci
et al., 2000, 2003).
MATERIALS AND METHODS
AREAS OF ENDEMISM
An area of endemism is defined as an area of
nonrandom distributional congruence among differ-
ent taxa. It is identified by the congruent distri-
butional boundaries of two or more species, where
congruence does not demand complete agreement
on those limits at all possible scales of mapping,
but relatively extensive sympatry is a prerequisite
(Platnick, 1991).
Areas of endemism used in this analysis are de-
fined primarily by Takhtajan (1986) and Thorne
(1993) and validated by other biogeographical stud-
ies (i.e., Dice, 1943; Rzedowski, 1978; Brown et
al., 1979, 1998; McLaughlin, 1989, 1992; Ayala et
al., 1993; Escalante Pliego et al., 1993; Fa & Mo-
rales, 1993; Li & Adair, 1994; Liebherr, 1994a, b;
Morrone et al., 1999; Marshall & Liebherr, 2000;
Morrone, 2001). Because the focus of this study is
on a major plant lineage that has diversified in arid
North America, we have used small, closely defined
areas within the Madrean area. Some taxa within
this lineage have distributions that extend beyond
the North American regions. For these we used the
more broadly defined Neotropical, East Palearctic,
and West Palearctic regions, since they fall outside
of our area of focus in North America. Africa and
Australia were not included because native North
American species of these three tribes occur in
these areas only as exotics. Table 2 lists the areas
of endemism alphabetically, with taxa of the three
target tribes endemic to each area. Full descrip-
tions of each area of endemism, including sample
plant and animal taxa endemic to each, are provid-
ed in Appendix 1. The areas are illustrated in Fig-
ure 1.
In some regions, the area delineations provided
by Takhtajan (1986) and Thorne (1993) proved
somewhat vague or difficult to interpret, and in
those cases we used additional resources to deter-
mine the boundaries. For example, we used the
geographical subdivisions found in The Jepson
Manual (Hickman, 1993) to more precisely delin-
eate the five regions in California (CAL, GBA,
MOJ, SON, and VAN; see Table 2 for area acro-
nyms). Similarly, we used the vegetational areas de-
scribed in Correll and Johnston (1970) to establish
the boundaries of the regions in Texas (APP, ATL,
CHI, NAP, and TAM). Additional sources used for
specific areas are referenced in the area descrip-
tion. In this way, distributional records could be
placed more precisely in the appropriate area of
endemicity.
TAXA ANALYZED
The primary data for this analysis are the distri-
butions of 173 native species of Onagraceae tribes
Epilobieae, Gongylocarpeae, and Onagreae inhab-
iting North America (Canada, Mexico, United
States; Table 1). The distributional data were taken
Volume 91, Number 1
2004
161Katinas et al.
Geographical Diversification
Table 1. List of species included in this analysis and source of distributional data (see text for details regarding
unpublished data). Gongylocarpus is listed here in tribe Onagreae; only recently (Levin et al., 2003) it was transferred
to tribe Gongylocarpeae. The number of each species corresponds with column numbers in the data matrix (Table 3).
Names of taxa are those currently in use, based on recent revisions. Two of the names, Oenothera deserticola and O.
purpusii, subsequently have been revised due to a nomenclatural problem (Wagner, 2004): Oenothera purpusii in the
sense used here will become O. deserticola, and the current O. deserticola will take a new name.
Taxa Source of information
TRIBE ONAGREAE
Camissonia Link Raven (1962, 1969)
1. C. andina (Nutt.) P. H. Raven
2. C. arenaria (A. Nelson) P. H. Raven
3. C. boothii (Douglas) P. H. Raven
4. C. breviflora (Torr. & A. Gray) P. H. Raven
5. C. brevipes (A. Gray) P. H. Raven
6. C. californica (Nutt. ex Torr. & A. Gray) P. H. Raven
7. C. campestris (Greene) P. H. Raven
8. C. cardiophylla (Torr.) P. H. Raven
9. C. chamaenerioides (A. Gray) P. H. Raven
10. C. cheiranthifolia (Hornem. ex Spreng.) Raim.
11. C. claviformis (Torr. & Fre?m.) P. H. Raven
12. C. confusa P. H. Raven
13. C. contorta (Douglas) Kearney
14. C. eastwoodiae (Munz) P. H. Raven
15. C. graciliflora (Hook. & Arn.) P. H. Raven
16. C. guadalupensis (S. Watson) P. H. Raven
17. C. hilgardii (Greene) P. H. Raven
18. C. hirtella (Greene) P. H. Raven
19. C. ignota (Jeps.) P. H. Raven
20. C. intermedia P. H. Raven
21. C. kernensis (Munz) P. H. Raven
22. C. lacustris P. H. Raven
23. C. lewisii P. H. Raven
24. C. minor (A. Nelson) P. H. Raven
25. C. multijuga (S. Watson) P. H. Raven
26. C. ovata (Nutt. ex Torr. & A. Gray) P. H. Raven
27. C. pallida (Abrams) P. H. Raven
28. C. palmeri (S. Watson) P. H. Raven
29. C. parvula (Nutt. ex Torr. & A. Gray) P. H. Raven
30. C. pterosperma (S. Watson) P. H. Raven
31. C. pubens (S. Watson) P. H. Raven
32. C. pusilla P. H. Raven
33. C. pygmaea (Douglas) P. H. Raven
34. C. refracta (S. Watson) P. H. Raven
35. C. robusta P. H. Raven
36. C. scapoidea (Torr. & A. Gray) P. H. Raven
37. C. strigulosa (Fisch. & C. A. Mey.) P. H. Raven
38. C. subacaulis (Pursh) P. H. Raven
39. C. tanacetifolia (Torr. & A. Gray) P. H. Raven
40. C. walkeri (A. Nelson) P. H. Raven
Calylophus Spach Towner (1977)
41. C. berlandieri Spach
42. C. hartwegii (Benth.) P. H. Raven
43. C. lavandulifolius (Torr. & A. Gray) P. H. Raven
44. C. serrulatus (Nutt.) P. H. Raven
45. C. toumeyi (Small) Towner
46. C. tubicula (A. Gray) P. H. Raven
Clarkia Pursh Lewis & Lewis (1955, except in *)
47. C. amoena (Lehm.) A. Nelson & J. F. Macbr.
162 Annals of the
Missouri Botanical Garden
Table 1. Continued.
Taxa Source of information
48. C. biloba (Durand) A. Nelson & J. F. Macbr.
49. C. concinna (Fisch. & C. A. Mey.) Greene
50. C. cylindrica (Jeps.) F. H. Lewis & M. R. Lewis
51. C. dudleyana (Abrams) J. F. Macbr.
52. C. epilobioides (Nutt. ex Torr. & A. Gray) A. Nelson & Macbr.
53. C. gracilis (Piper) A. Nelson & J. F. Macbr.
54. *C. heterandra (Torr.) F. H. Lewis & P. H. Raven
55. C. lassenensis (Eastw.) F. H. Lewis & M. R. Lewis
56. C. modesta Jeps.
57. *C. mosquini E. Small
58. C. pulchella Pursh
59. C. purpurea (Curtis) A. Nelson & J. F. Macbr.
60. C. rhomboidea Douglas
61. *C. rostrata W. S. Davis
62. C. speciosa F. H. Lewis & M. R. Lewis
63. *C. tembloriensis Vasek
64. C. unguiculata Lindl.
Lewis (1993)
Lewis (1993)
Lewis (1993)
Lewis (1993)
65. C. xantiana A. Gray
Gaura L. Raven & Gregory (1972)
66. G. angustifolia Michx.
67. G. biennis L.
68. G. boquillensis P. H. Raven & D. P. Greg.
69. G. brachycarpa Small
70. G. calcicola P. H. Raven & D. P. Greg.
71. G. coccinea Pursh
72. G. drummondii (Spach) Torr. & A. Gray
73. G. filipes Spach
74. G. hexandra Ortega
75. G. longiflora Spach
76. G. mckelveyae (Munz) P. H. Raven & D. P. Greg.
77. G. mutabilis Cav.
78. G. neomexicana Wooton
79. G. parviflora Douglas ex Lehm.
80. G. sinuata Nutt. ex Ser.
81. G. suffulta Engelm. ex A. Gray
82. G. villosa Torr.
Gayophytum A. Juss. Lewis & Szweykowski (1964)
83. G. decipiens F. H. Lewis & Szweykowski
84. G. diffusum Torr. & A. Gray
85. G. heterozygum F. H. Lewis & Szweykowski
86. G. humile A. Juss.
87. G. racemosum Torr. & A. Gray
88. G. ramosissimum Torr. & A. Gray
Gongylocarpus Cham. & Schltdl. (transferred to Gongylocarpeae; Levin et al., 2003)
89. G. rubricaulis Schltdl. & Cham. Carlquist & Raven (1966)
Oenothera L.
90. O. albicaulis Pursh
91. O. biennis L.
92. O. brachycarpa A. Gray
93. O. caespitosa Nutt.
W. L. Wagner (unpublished data)
Dietrich et al. (1997)
W. L. Wagner (unpublished data)
Wagner et al. (1985)
94. O. californica (S. Watson) S. Watson
95. O. cavernae Munz
96. O. cordata J. W. Loudon
W. L. Wagner (unpublished data)
Wagner et al. (1985)
Dietrich & Wagner (1988)
97. O. coronopifolia Torr. & A. Gray
98. O. deltoides Torr. & Fre?m.
W. L. Wagner (unpublished data)
W. L. Wagner (unpublished data)
Volume 91, Number 1
2004
163Katinas et al.
Geographical Diversification
Table 1. Continued.
Taxa Source of information
99. O. deserticola (Loes.) Munz
100. O. dissecta A. Gray ex S. Watson
101. O. drummondii Hook.
102. O. elata Kunth
103. O. epilobiifolia Kunth
104. O. falfurriae W. Dietr. & W. L. Wagner
105. O. flava (A. Nelson) Garrett
106. O. fruticosa L.
107. O. grandiflora L?He?r.
Wagner (2004, unpublished data)
Wagner (1984)
Dietrich & Wagner (1988)
Dietrich et al. (1997)
W. L. Wagner (unpublished data)
Dietrich & Wagner (1988)
W. L. Wagner (unpublished data)
Straley (1977)
Dietrich et al. (1997)
108. O. grandis (Britton) Smyth
109. O. heterophylla Spach
110. O. howardii (A. Nelson) W. L. Wagner
111. O. humifusa Nutt.
112. O. jamesii Torrey & A. Gray
Dietrich & Wagner (1988)
Dietrich & Wagner (1988)
W. L. Wagner (unpublished data)
Dietrich & Wagner (1988)
Dietrich et al. (1997)
113. O. kunthiana (Spach) Munz
114. O. laciniata Hill
115. O. latifolia (Rydb.) Munz
116. O. linifolia Nutt.
117. O. longissima Rydb.
118. O. macrocarpa Nutt.
119. O. macrosceles A. Gray
120. O. mexicana Spach
121. O. nuttallii Sweet
122. O. nutans G. F. Atk. & Bartlett
W. L. Wagner (unpublished data)
Dietrich & Wagner (1988)
W. L. Wagner (unpublished data)
Straley (1977)
Dietrich et al. (1997)
W. L. Wagner (unpublished data)
Dietrich et al. (1985)
Dietrich & Wagner (1988)
W. L. Wagner (unpublished data)
Dietrich et al. (1997)
123. O. oakesiana (A. Gray) J. W. Robbins ex S. Watson & J. M. Coulter
124. O. pallida Lindl.
125. O. parviflora L.
126. O. pennellii Munz
127. O. perennis L.
128. O. pilosella Raf.
129. O. primiveris A. Gray
130. O. pubescens Willd. ex Spreng.
131. O. purpusii Munz
Dietrich et al. (1997)
W. L. Wagner (unpublished data)
W. L. Wagner (unpublished data)
W. L. Wagner (unpublished data)
Straley (1977)
Straley (1977)
Wagner (1986, unpublished data)
Dietrich & Wagner (1988)
Wagner (2004, unpublished data)
132. O. rhombipetala Nutt. ex Torr. & A. Gray
133. O. rosea L?He?r. ex Aiton
134. O. spachiana Torr. & A. Gray
135. O. speciosa Nutt.
136. O. tetraptera Cav.
137. O. triloba Nutt.
Dietrich & Wagner (1988)
W. L. Wagner (unpublished data)
Straley (1977)
W. L. Wagner (unpublished data)
W. L. Wagner (unpublished data)
W. L. Wagner (unpublished data)
138. O. tubifera Ser.
139. O. villosa Thunb.
W. L. Wagner (unpublished data)
W. L. Wagner (unpublished data)
Stenosiphon Spach
140. S. linifolius (Nutt.) Heynh. Great Plains Flora Assoc. (1986)
TRIBE EPILOBIEAE
Chamerion (Raf.) Raf. Hoch (1993)
141. C. angustifolium L.
142. C. latifolium L.
Mosquin (1966)
Small (1968)
Epilobium L. Hoch (1986, 1993, unpublished (see
text))
143. E. anagallidifolium Lam.
144. E. arcticum Sam.
145. E. brachycarpum C. Presl
146. E. canum (Greene) P. H. Raven
147. E. ciliatum Raf.
148. E. clavatum Hausskn.
164 Annals of the
Missouri Botanical Garden
Table 1. Continued.
Taxa Source of information
149. E. coloratum Spreng.
150. E. davuricum Fisch. ex Hornem.
151. E. densiflorum (Lindl.) Hoch & P. H. Raven Raven & Moore (1965)
152. E. denticulatum Ruiz & Pav.
153. E. foliosum (Nutt. ex Torr. & A. Gray) Suksd.
154. E. glaberrimum Barbey
155. E. halleanum Hausskn.
156. E. hornemannii Rchb.
157. E. lactiflorum Hausskn.
158. E. leptocarpum Hausskn.
159. E. leptophyllum Raf.
160. E. luteum Pursh
161. E. minutum Lindl. ex Lehm.
162. E. mirabile Trel.
163. E. nevadense Munz
164. E. obcordatum A. Gray
165. E. oregonense Hausskn.
166. E. pallidum (Eastw.) Hoch & P. H. Raven Raven & Moore (1965)
167. E. palustre L.
168. E. pygmaeum (Speg.) Hoch & P. H. Raven Raven & Moore (1965)
169. E. saximontanum Hausskn.
170. E. smithii H. Le?v.
171. E. strictum Muhl.
172. E. suffruticosum Nutt.
173. E. torreyi (S. Watson) Hoch & P. H. Raven Raven & Moore (1965)
from recent or unpublished taxonomic revisions,
supplemented with specimen label data from the
herbaria at MO and US (Table 3). Distribution re-
cords for Epilobium derive from nearly 100,000
specimens from more than 100 herbaria consulted
in preparation for a revision (Hoch et al., unpub-
lished); these records served as the basis for Epi-
lobium treatments in The Jepson Manual (Hoch,
1993), the Flora of the Great Plains (Hoch, 1986),
and other recent floras. Records for several sections
of Oenothera for which taxonomic revisions are not
yet published (cited in Table 1 as ??Wagner, unpub-
lished data??) are derived from several sources. All
unpublished Oenothera distributions except for
those of section Anogra are based on approximately
4500 collections from more than 100 herbaria bor-
rowed for those revisions. For the 10 species of
section Anogra, distributions derive from some 250
collections at US and MO, supplemented by addi-
tional collections examined for The Jepson Manual
project (Wagner, 1993). We have excluded from our
distributional analysis specimens that were culti-
vated and/or appear far outside the established
range in human-disturbed habitats. Species that oc-
cur only in one area of endemism are not infor-
mative in a Parsimony Analysis of Endemicity
(PAE) regarding area relationships and therefore
are excluded from the analysis. However, they pro-
vide support for the delimitation of areas of ende-
mism and are listed in Table 2. For example, the
monotypic genus Xylonagra is endemic to Central
Baja California and thus is used to circumscribe
the Sonoran (SON) region.
Although almost all of the genera of Epilobieae,
Gongylocarpeae, and Onagreae are endemic to or
have had their major basal radiation in the Mad-
rean Floristic Region of southwestern North Amer-
ica, many species of these tribes, especially in Epi-
lobium and Oenothera, occur outside of North
America. If native North American species also
have a native distribution outside of North America,
those distributions are included in the data matrix
in the appropriate area (NE, WP, or EP). However,
if a species occurs as a native only outside of North
America, it has been excluded from this analysis.
These excluded taxa include in Epilobieae 6 Eur-
asian species of Chamerion and 125 species of Epi-
lobium (large groups endemic to South America,
Eurasia, and Australasia), and in Onagreae, 1 spe-
cies each of Camissonia (C. dentata), Clarkia (C.
tenella), and Gayophytum (G. micranthum), and 39
species of Oenothera, virtually all endemic to South
America. In Epilobium and Oenothera, we have ex-
cluded 9 species (E. billardierianum and E. ko-
Volume 91, Number 1
2004
165Katinas et al.
Geographical Diversification
Table 2. Alphabetical list of areas of endemism used in this analysis, and taxa of tribes Epilobieae, Gongylocarpeae,
and Onagreae (Onagraceae) endemic to specific individual areas (see Table 1 for sources of distributional data). See
Appendix 1 for full descriptions of the areas and references; numbers in parentheses refer to Appendix 1.
Acronym/Area of endemism Endemic taxa
APP/Appalachian (3) Gaura demareei P. H. Raven & D. P. Greg.; Oenothera argillicola Mack.
ARC/Arctic (1) ?
ATL/Atlantic and Gulf Coastal (4) Gaura lindheimeri Engelm. & A. Gray; Oenothera clelandii W. Dietr., P.
H. Raven & W. L. Wagner, O. curtissii Small
CAL/Californian (9) Camissonia benitensis P. H. Raven, C. bistorta (Nutt. ex Torr. & A.
Gray) P. H. Raven, C. hardhamiae P. H. Raven, C. integrifolia P. H.
Raven; C. luciae P. H. Raven, C. micrantha (Hornem. ex Spreng.) P.
H. Raven; Clarkia affinis F. H. Lewis & M. R. Lewis, C. borealis E.
Small, C. bottae (Spach) F. H. Lewis & M. R. Lewis, C. breweri (A.
Gray) Greene, C. davyi (Jepson) F. H. Lewis & M. R. Lewis, C. deli-
cata (Abrams) A. Nelson & J. F. Macbride, C. franciscana F. H.
Lewis & P. H. Raven, C. imbricata F. H. Lewis & M. R. Lewis, C.
joloensis D. R. Parn., C. lewisii P. H. Raven & D. R. Parn., C. pros-
trata F. H. Lewis & M. R. Lewis, C. rubicunda (Lindl.) F. H. Lewis
& M. R. Lewis, C. similis F. H. Lewis & W. R. Ernst; Epilobium
cleistogamum (Curran) P. Hoch & P. H. Raven; Gayophytum oligo-
spermum F. H. Lewis & Szweyk.
CAN/Canadian (2) ?
CHI/Chihuahuan (12) Gaura macrocarpa Rothr.; Oenothera havardii S. Watson, O. neomexi-
cana (Small) Munz, O. organensis Munz, O. platanorum P. H. Raven
& D. R. Parn., O. riskindii W. L. Wagner, O. texensis P. H. Raven &
D. R. Parn.
EP/East Palearctic (20) ? (some endemics, but outside of North American study group)
GBA/Great Basin (8) Camissonia atwoodii Cronquist, C. confertiflora (P. H. Raven) P. H. Ra-
ven, C. exilis (P. H. Raven) P. H. Raven, C. gouldii P. H. Raven, C.
heterocroma (S. Watson) P. H. Raven, C. megalantha (Munz) P. H.
Raven, C. nevadensis (Kellogg) P. H. Raven, C. parryi (S. Watson) P.
H. Raven, C. speculicola (P. H. Raven) P. H. Raven
MAS/Mexican Altiplano (16) ?
MOJ/Mojavean (10) Camissonia munzii (P. H. Raven) P. H. Raven
NAP/North American Prairies (5) Gaura triangulata Buckl.; Oenothera canescens Torr. & Fre?m., O. coryi
W. L. Wagner, O. engelmannii (Small) Munz, O. harringtonii W. L.
Wagner, Stockh. & W. M. Klein
NE/Neotropical (19) ? (some endemics, but outside of North American study group)
ROC/Rocky Mountain (7) Oenothera acutissima W. L. Wagner, O. psammophila (A. Nelson & J. F.
Macbr.) W. L. Wagner, Stockh. & W. M. Klein
SMO/Sierra Madre Occidental (14) Epilobium maysillesii Munz; Oenothera maysillesii Munz, O. tamrae W.
Dietr. & W. L. Wagner
SMR/Sierra Madre Oriental (17) Oenothera muelleri Munz, O. stubbei W. Dietr., P. H. Raven & W. L.
Wagner
SMS/Sierra Madre del Sur (18) ?
SON/Sonoran (11) Camissonia angelorum (S. Watson) P. H. Raven, C. crassifolia (Greene)
P. H. Raven, C. proavita P. H. Raven, C. sceptrostigma (Brandegee)
P. H. Raven; Gongylocarpus fruticulosus (Benth.) K. Brandegee; Oen-
othera arizonica (Munz) W. L. Wagner, O. brandegeei (Munz) P. H.
Raven, O. breedlovei W. Dietr. & W. L. Wagner, O. wigginsii W. M.
Klein; Xylonagra arborea (Kellogg) J. D. Smith & J. N. Rose
TAM/Tamaulipan (13) ?
TMV/Trans-Mexican Volcanic Belt (15) ?
VAN/Vancouverian (6) Camissonia sierrae P. H. Raven; Clarkia arcuata (Kellogg) A. Nelson &
J. F. Macbr., C. australis E. Small, C. exilis F. H. Lewis & Vasek, C.
lingulata F. H. Lewis & M. R. Lewis, C. mildrediae (Heller) F. H.
Lewis & M. R. Lewis, C. springvillensis Vasek, C. stellata Mosquin,
C. virgata Greene, C. williamsonii (Durand & Hilg.) F. H. Lewis &
M. R. Lewis; Epilobium howellii P. Hoch, E. nivium T. S. Brandegee,
E. oreganum Greene, E. rigidum Hausskn., E. septentrionale (D. D.
Keck) Bowman & P. Hoch, E. siskiyouense (Munz) P. Hoch & P. H.
Raven; Gayophytum eriospermum Coville; Oenothera wolfii (Munz) P.
H. Raven, O. xylocarpa Coville
WP/West Palearctic (21) ? (some endemics, but outside of North American study group)
166 Annals of the
Missouri Botanical Garden
Figure 1. Areas of endemism as delimited for the historical biogeographic analysis and used to code the distri-
butional data for each species. The areas were drawn in Photoshop 7.0 by Alice Tangerini on a base map from ArcMap
8.2 (ESRI) with a North American Lambert conformal conic projection. The floristic regions are based primarily on
Takhtajan (1986) and Thorne (1993), with other modifications as described in the text.
marovianum from Australasia and E. hirsutum, E.
montanum, E. obscurum, and E. parviflorum from
Eurasia, O. glazioviana, a hybrid of recent origin
in Europe, and O. mollissima and O. stricta from
South America) because all of them clearly have
been introduced into North America in historical
time.
PARSIMONY ANALYSIS OF ENDEMICITY (PAE)
Parsimony analysis of endemicity or PAE (Ro-
sen, 1988; Rosen & Smith, 1988) is an historical
biogeographical approach that seeks to identify the
distributional pattern of organisms. It classifies lo-
calities, quadrats, or areas (which are analogous to
taxa) by their shared taxa (which are analogous to
characters) according to the most parsimonious so-
lution resulting in a hierarchical classification of
the geographic units (Morrone & Crisci, 1995; Cris-
ci et al., 2000, 2003). Rosen (1988) originally pro-
posed the method using localities as study units.
Craw (1988) and Cracraft (1991) presented a vari-
ation of the method using areas of endemism as
study units to identify the hierarchical information
contained in the geographical distribution of organ-
Volume 91, Number 1
2004
167Katinas et al.
Geographical Diversification
isms to establish area relationships. Indeed, Mc-
Laughlin (1992) suggested that areas are actually
arranged in a natural hierarchy.
The variation of the methodology proposed by
Craw (1988) and Cracraft (1991) using areas of en-
demism included taxonomic information in the ma-
trix by adding columns for higher taxonomic cate-
gories or phylogenetic information. Thus, the
resulting matrix consisted of areas 3 species dis-
tributions plus generic distributions. However, as
Crisci et al. (2000) observed, adding phylogenetic
or taxonomic information to the matrix is a misuse
of Brooks parsimony analysis (Brooks et al., 2001),
which is a technique that does not utilize phylo-
genetic data specifically. Therefore, we use areas of
endemism as our units of study and species distri-
butions as the characters of those areas, but ex-
clude the information on supraspecific taxa.
PAE cladograms represent nested sets of areas
in which terminal dichotomies represent two areas
between which the most recent biotic interchange
has occurred (Morrone & Crisci, 1995). Craw
(1988) suggested that ??character?? reversions in the
cladogram could be interpreted biogeographically
as extinctions, and parallelisms as dispersions. This
analysis was carried out using PAUP*, vers. 4.0b10
(Swofford, 2001), applying the branch-and-bound
and deltran options. If more than one tree results
from the analysis, a strict consensus tree is con-
structed. As proposed by Rosen (1988), the clad-
ogram was rooted with a hypothetical area coded
with all zeros. The bootstrap method (Felsenstein,
1985) was employed to evaluate the reliability of
the estimates; 100 replicates were performed. We
used the software MacClade 4.0 (Maddison & Mad-
dison, 2000) to generate the data matrix and as a
tool to analyze the taxa distribution on the tree(s).
PANBIOGEOGRAPHY (COMPATIBILITY TRACK
METHOD)
Croizat (1958) postulated that geographic barri-
ers evolve together with biotas. The panbiogeo-
graphic approach (Croizat, 1958, 1981) consists of
plotting distributions of taxa on maps and connect-
ing their separate distributional areas together with
lines called individual tracks. When individual
tracks coincide, the resulting summary lines are
considered generalized tracks, which indicate the
pre-existence of ancestral biotas that became frag-
mented by tectonic and/or climatic changes. At the
same time, generalized tracks provide spatial cri-
teria for biogeographic homology (Grehan, 1988a,
b; Morrone & Crisci, 1995). When two or more gen-
eralized tracks intersect, that area is called a node.
Nodes are dynamic biogeographic boundaries
where remnant fragments of different ancestral bi-
otas come into contact. Nodes are biogeographically
interesting because they are composite regions that
represent an intersection of different biogeograph-
ical and ecological histories.
Analytical developments by McAllister et al.
(1986), Page (1987), Connor (1988), Craw (1989),
and Henderson (1990, 1991) used graph theory to
provide objective and quantitative methods for
drawing and comparing tracks, including the com-
patibility track method applied here. This method
was developed by Craw (1988, 1989), based on the
concept of distributional compatibility (Connor,
1988; Craw, 1989). Individual tracks are treated as
biogeographic hypotheses of relationship among lo-
calities or distribution areas. Two or more individ-
ual tracks are regarded as being compatible only if
they result in the same pairwise comparison or if
one track is a subset of the other. This method is
analogous to character compatibility (Meacham,
1984). However, in the track compatibility method,
nonoverlapping tracks are incompatible, whereas
they would be compatible under the original taxo-
nomic concept. The compatibility track method ba-
sically consists of constructing a matrix (areas vs.
taxa), where each taxon is scored as present (1) or
absent (0) in each area, and applying compatibility
analysis software to find the largest clique(s) of
compatible tracks. The method involves finding a
simple form of spanning tree linking localities or
distribution areas. The tree is constructed from the
largest clique of compatible distributions in a dis-
tributional compatibility matrix and is based on the
original concept of compatibility (nonoverlapping
tracks are also considered compatible). Therefore,
using a restricted concept of compatibility (only in-
dividual tracks that are either included within or
replicated by one another are compatible) the tree
(5 clique) could contain more than one generalized
track. In this case, multiple generalized tracks
(groups) found in one clique will be formed only by
areas that are exclusive of each generalized track.
If more than one largest clique or several cliques
of considerable size are found, then a hypothesis of
existence of several generalized tracks linking the
localities or distribution areas in more than one way
can be considered (areas can be members of more
than one generalized track at the same time). Al-
ternatively, the intersection (i.e., those individual
tracks common to all the largest cliques) can also
be identified as a generalized track (Craw, 1990).
For more details and other applications of this
method see Craw (1988, 1989), Morrone and Crisci
168 Annals of the
Missouri Botanical Garden
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Volume 91, Number 1
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169Katinas et al.
Geographical Diversification
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00
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00
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00
0
170 Annals of the
Missouri Botanical Garden
(1990, 1995), Craw et al. (1999), and Crisci et al.
(2000, 2003).
In this analysis we use the same areas of ende-
mism and the same data matrix (Table 3) that we
used in the PAE analysis. The analysis of the data
matrix of 21 areas of endemism versus individual
tracks of 173 taxa (Table 3) was carried out with
SECANT 2.2 (Salisbury, 1999). SECANT identifies
all groups of cladistically compatible characters.
Individual tracks were treated here as binary char-
acters ordered with absence as the ??ancestral?? state
for each (5 outgroup with all zeros), and presence
as state 1.
RESULTS
PARSIMONY ANALYSIS OF ENDEMICITY
The analysis of the data matrix (Table 3) with
PAUP*4.0b10 generated four area cladograms (Fig.
2) with 377 steps, consistency index (CI) 5 0.459,
and retention index (RI) 5 0.619, which differed
in the relationships among most Mexican areas
SMO, TMV, MAS, SMR, SMS; in the relationship
of the Neotropical area (NE) either with the Mexi-
can areas (Fig. 2B?D) or with the eastern North
American areas APP, ATL, NAP, CHI, and TAM
(Fig. 2A); in the relationship of APP, ATL, NAP,
CHI, and TAM either with the Mexican areas (Fig.
2A?B) or with the western areas VAN, CAL, ROC,
GBA, SON, and MOJ (Fig. 2C?D); and in the re-
lationship of Tamaulipas (TAM) either with Chi-
huahua (CHI) (Fig. 2C?D), or with APP, ATL, NAP,
and CHI (Fig. 2A?B).
The strict consensus of the four trees (Fig. 3)
shows the following area relationships: (1) ((Arctic,
Canadian) West Palearctic, East Palearctic) forms
the basalmost lineage, sister to the remaining areas;
(2) (((Appalachian, Atlantic) North American Prai-
ries) Chihuahuan, Tamaulipas); (3) ((((Vancouveri-
an, Californian) (Rocky Mountains, Great Basin))
Sonoran) Mojavean); (4) ((Mexican Altiplano, Sierra
Madre Oriental) Sierra Madre Occidental, Trans-
Mexican Volcanic Belt, Sierra Madre del Sur); and
(5) the Neotropical as one single branch. The last
four branches (2?5) constitute a polytomy. Thus,
the strict consensus cladogram generated by
PAUP*4.0b10 shows four main groups (Fig. 4):
northern North America, eastern North America,
western North America, and the central Mexican
areas.
The percentage of 100 bootstrap replicates dem-
onstrates that strength of support for nodes varies
considerably. Many branches have less than 50%
support, but others, particularly in eastern and
western North America, have stronger support. The
most strongly supported branches in order are: 99%
(APP?ATL), 98% (VAN?CAL), 96% (VAN, CAL,
ROC, GBA), 79% (ROC?GBA), 78% (APP, ATL,
NAP, CHI, TAM), 62% (VAN, CAL, ROC, GBA,
SON, MOJ), 61% (APP, ATL, NAP), and 60%
(ARC, CAN, WP, EP). The weakness and strength
of bootstrap values may reflect the strong concen-
tration of taxa in northern Mexico and southwestern
United States, and lower concentration in areas
more distant from that area.
PANBIOGEOGRAPHY (COMPATIBILITY TRACK
METHOD)
Applying the SECANT 2.2 program to the data
matrix (Table 3) resulted in 4 largest cliques, each
with 51 individual tracks. The intersection (those
49 individual tracks common to the 4 largest
cliques) is considered as the fifth large clique.
These 5 cliques contain a total of 11 generalized
tracks. The first clique contains 2 generalized
tracks, the second clique contains 2, the third
clique contains 3, the fourth clique contains 2, and
the intersection contains 2 generalized tracks.
Since many of these tracks in different cliques are
the same, the 11 generalized tracks can be reduced
to 3 generalized tracks: 2 strongly supported
(??East??/green and ??West??/purple in Fig. 5), and 1
weakly supported (??South??/orange in Fig. 5). The
northern regions (ARC, CAN, EP, and WP) and two
areas in Mexico (SMO and TMV) are not part of
these supported generalized tracks, and are shown
as white in Figure 5.
The first (??East??) strong generalized track in-
cludes eastern North American areas (ATL, APP,
CHI, NAP, TAM), and is strongly supported by 17
individual tracks from taxa in 3 genera, namely,
Calylophus berlandieri (taxon 41); Gaura biennis
(67), G. brachycarpa (69), G. filipes (73), G. longi-
flora (75), G. sinuata (80), and G. suffulta (81); and
Oenothera cordata (96), O. falfurriae (104), O.
grandiflora (107), O. grandis (108), O. heterophylla
(109), O. linifolia (116), O. mexicana (120), O. nu-
tans (122), O. spachiana (134), and O. speciosa
(135).
The second (??West??) strong generalized track in-
cludes the western North American areas (CAL,
GBA, MOJ, ROC, SON, VAN), and is supported by
31 individual tracks from taxa in 4 genera, namely,
Camissonia boothii (taxon 3), C. campestris (7), C.
graciliflora (15), C. lacustris (22), C. ovata (26), and
C. pubens (26); all species of Clarkia (47?65) ex-
cept for C. epilobioides (52), C. pulchella (58), and
C. purpurea (59); Gayophytum decipiens (83) and G.
heterozygum (85); and Epilobium clavatum (148), E.
Volume 91, Number 1
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171Katinas et al.
Geographical Diversification
Figure 2. Four most parsimonious cladograms (A?D) resulting from the parsimony analysis of endemicity (PAE)
analysis after applying PAUP* vers. 4.0b10. Trees are 377 steps, CI 5 0.459, and RI 5 0.619. Area acronyms
correspond to those in Figure 1 and Table 2.
172 Annals of the
Missouri Botanical Garden
Figure 3. Strict consensus cladogram of the four cladograms obtained in the parsimony analysis of endemicity
(PAE). Bootstrap support values are shown above the branches. Area acronyms correspond to those in Figure 1 and
Table 2.
Volume 91, Number 1
2004
173Katinas et al.
Geographical Diversification
Figure 4. Strict consensus cladogram of the four cladograms obtained in the parsimony analysis of endemicity
superimposed onto the map with the areas of endemism. The tree branches delineate four main groups of areas: northern
(ARC, CAN, EP, WP), eastern North America (APP, ATL, NAP, CHI, TAM), western North America (VAN, CAL, ROC,
GBA, SON, MOJ), and southern North America (SMO, TMV, MAS, SMR, SMS). Areas correspond to those in Figure
1 and Table 2.
densiflorum (151), E. glaberrimum (154), E. minu-
tum (161), E. oregonense (165), E. pallidum (166),
and E. torreyi (173).
The third (??South??) generalized track includes
some of the Mexican areas (MAS, SMR, SMS) and
the Neotropical area (NE), with support from only
2 individual tracks, of Oenothera deserticola (taxon
99) and O. epilobiifolia (103). The South general-
ized track is considerably weaker than the previous
two, since it is supported by many fewer individual
tracks. The Neotropical area is supported as part
of the East generalized track by Oenothera lacinia-
ta (taxon 114). The Trans-Mexican Volcanic Belt
(TMV) is supported as part of the South generalized
track by Oenothera kunthiana (taxon 113). Several
Mexican areas (SMS, TMV, MAS) are supported as
part of the East generalized track by Gaura drum-
mondii (taxon 72) and Oenothera jamesii (112). As
noted above, the Sierra Madre Occidental (SMO)
does not form part of any generalized track.
174 Annals of the
Missouri Botanical Garden
Figure 5. Distributional patterns after applying track compatibility analysis: a strongly supported Eastern gener-
alized track including APP, ATL, CHI, NAP, and TAM, shown in green; a strongly supported Western generalized track,
including CAL, GBA, MOJ, ROC, SON, and VAN, shown in purple; and a weakly supported Mexican and Neotropic
generalized track including MAS, NE, SMR, and SMS, shown in orange. The areas ARC, CAN, SMO, and TMV, shown
in white, and the two non-North American areas EP and WP, do not form part of any generalized track. Area acronyms
correspond to those in Figure 1 and Table 2.
These data weakly support the Neotropical area
(NE) as a panbiogeographic node in the distribu-
tional history of Onagreae, Gongylocarpeae, and
Epilobieae, since there is some support for its in-
clusion in both the East and South generalized
tracks.
The program SECANT 2.2 also found 9 cliques
each with 50 individual tracks. The analysis of
these 9 cliques resulted in the same generalized
tracks that we found among the five largest cliques,
with the exception of one generalized track found
in only one of the 9 cliques. This additional track
includes the areas CHI and TAM, supported by
Gaura boquillensis (taxon 68), Oenothera macros-
celes (119), and O. pennellii (126).
Most of the genera of Epilobieae and Onagreae
support at least one of the generalized tracks found
in this analysis, i.e., Calylophus, Gaura, and Oen-
othera belong to the East track, and Camissonia,
Clarkia, Gayophytum, and Epilobium to the West
track. Several other genera, including Chamerion
(Epilobieae; two species), Gongylocarpus (Gongy-
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2004
175Katinas et al.
Geographical Diversification
locarpeae; two species), and Stenosiphon (Ona-
greae; one species) do not form part of any gener-
alized track.
DISCUSSION
The historical biogeography of North America
has long been a focus of botanists attempting to find
general patterns of relationships within North
America and between North America and other
continents. The present-day geographical distribu-
tion of Epilobieae, Gongylocarpeae, and Onagreae
and the biogeographic patterns generated by those
distributions may provide clues to understanding
the high diversity and endemicity of these three
tribes in North America, as well as the history of
the areas involved.
DISTRIBUTIONAL PATTERNS
The application of Parsimony Analysis of En-
demicity (PAE) to the species distribution of Epi-
lobieae, Gongylocarpeae, and Onagreae delimits
four major regions: northern North America; east-
ern North America; western North America; and
central Mexico (Fig. 4). Three of them (eastern
North America, western North America, and central
Mexico) are also found in the compatibility track
analysis. Comparison of these with the higher re-
gional floristic categories in the schemes of Takh-
tajan (1986) and Thorne (1993) suggests the follow-
ing differences and similarities. (1) Our northern
North American region coincides with the Circum-
boreal region of Takhtajan and Thorne. (2) Our
eastern North American region corresponds to the
North American Atlantic region of Takhtajan and
Thorne, with the addition of the Tamaulipas (TAM)
and Chihuahua (CHI) areas. Miranda and Sharp
(1950) proposed such an affinity from distributions
of many plant species, and they and Berry (1930)
suggested that this shared flora was derived from
the Eocene Wilcox flora of the Mississippi Embay-
ment. (3) The Rocky Mountain and Madrean re-
gions of Takhtajan and Thorne show different affin-
ities in our analysis. Their regions proposed close
affinities between ROC and VAN, and among CAL,
GBA, and the Sonoran Province, whereas our re-
sults link VAN with CAL and ROC with GBA. Ra-
ven and Axelrod (1978) considered the Vancouver-
ian (VAN) and Californian (CAL) areas to be closely
related since they share a flora comprising a mix-
ture of northern temperate elements and xeric,
southern elements, with a very high degree of en-
demism. Furthermore, Axelrod and Raven (1985)
also considered the Rocky Mountains (ROC) and
Great Basin (GBA) areas to be close because Cor-
dilleran taxa spread into the western Great Basin
largely after 14 m.y. ago as the climate became
drier, summer rains decreased, and eastern exotic
taxa were eliminated. (4) Our central Mexican areas
coincide with the Mexican Highlands Province of
Takhtajan and Thorne. The lower level of resolution
among the central Mexican areas observed in the
consensus PAE cladogram is most likely due to the
relatively few species of Epilobieae, Gongylocar-
peae, and Onagreae distributed there.
The relationships of the Madrean and other
North American regions to the Neotropical (NE) are
particularly complex, which is reflected in the am-
biguous position of NE in the four shortest trees
(Fig. 2). Indeed, NE could be considered a panbi-
ogeographic node in our study. Three species (Gau-
ra angustifolia [taxon 66], Oenothera humifusa
[111], and O. laciniata [114]) otherwise restricted
to the East region reach NE only at the southern
tip of Florida, and another eastern species, Epilob-
ium coloratum (149), occurs on Hispaniola (in NE),
apparently by long-distance dispersal. These taxa
provide support for NE as sister to the East region
(Fig. 2A). A single species, Gayophytum humile
(86), found primarily in the western region (VAN-
CAL-ROC-GBA), also occurs in NE, apparently as
a result of long-distance dispersal to central Chile
and Argentina (Lewis & Szweykowski, 1964). Most
of the connections of North American regions with
NE, however, are through the Mexican region (Fig.
2B?D), almost always by close adjacent dispersal
in western and southern Mexico, extending south
to Central and sometimes South America. Recent
phylogenetic analysis of Onagraceae (Levin et al.,
2003, 2004) suggests the following: (1) the imme-
diate sister clade to the Gongylocarpeae 1 Epilo-
bieae 1 Onagreae is a branch with Lopezia (Lo-
pezieae) and Megacorax (unplaced), both found
primarily or exclusively in the central Mexican re-
gion, with some Lopezia species extending to NE;
and (2) each of the three successive basal clades
of the family, namely Fuchsia 1 Circaea, Hauya,
and Ludwigia, have primary or exclusive distribu-
tions in NE. Circaea, with its circumboreal distri-
bution and absence from NE, is a notable excep-
tion; however, it forms a strongly supported clade
with Fuchsia. A detailed analysis of biogeographi-
cal patterns in Onagraceae using phylogenetic in-
formation is now in progress.
The distributions of numerous species do not co-
incide with the major patterns found in the PAE
and track compatibility analysis. In general, these
inconsistencies can result from one of three types
of processes, namely, dispersal, vicariance, or ex-
tinction affecting one or few species. The predom-
176 Annals of the
Missouri Botanical Garden
inant process in our study appears to be short-dis-
tance dispersal into geographically contiguous but
unrelated areas. This may involve large-scale dis-
persal, but more often involves only a few or even
one population(s) in the adjacent area. For exam-
ple, many species with distributions in the East
North American region often extend into the CAN
area [North region; e.g., Oenothera biennis (91), O.
fruticosa (106), O. parviflora (125)], or into ROC
[West region; e.g., Calylophus serrulatus (44), Oen-
othera nuttallii (121)], or to the south into the Mex-
ican region [e.g., Gaura drummondii (72), Oenoth-
era jamesii (112)]. Similarly, some western species
reach CAN [Camissonia breviflora (4)] or even ARC
[along the southwest coast of Alaska; Epilobium lep-
tocarpum (158), E. luteum (160)] in the northern
region, or CHI [Camissonia chamaenerioides (9),
Epilobium canum (146)] or NAP [Camissonia an-
dina (1), C. subacaulis (38), Gayophytum ramosis-
simum (88)] in the East region. One particularly
clear example of adjacent dispersal concerns Oen-
othera primiveris (129); in the West region of
primary distribution (GBA, SON, MOJ), most pop-
ulations are large-flowered and outcrossing (includ-
ing some that are self-incompatible), whereas the
populations in CHI (East region) are small-flowered
and autogamous (Wagner, unpublished data).
Some distributions that seem to represent adja-
cent dispersal may in fact have another explana-
tion. For example, Oenothera villosa (taxon 139) oc-
curs widely in both the western and eastern regions,
suggesting adjacent dispersal. However, genome
and cytological analysis (Dietrich et al., 1997) of
this permanent translocation heterozygote species
shows that populations in the western and eastern
regions, which currently are treated as subspecies,
derived independently from different populations of
Oenothera elata (102). Nevertheless, they inter-
grade so extensively in the transition area between
ROC and NAP that they are best treated as sub-
species of a single species.
Several taxa may represent examples of long-dis-
tance dispersal. For example, Epilobium saximon-
tanum (169), found primarily in the western region
(ROC, GBA, VAN) with near outliers in the eastern
region (NAP, CHI), also occurs in eastern CAN
(Newfoundland) and ARC (Ungava Bay, Quebec) in
the northern region. This highly disjunct pattern is
not found in other species and seems best ex-
plained as a case of long-distance dispersal. The
distribution of Calylophus lavandulifolius (43) is
unusual in several ways: it appears ??bimodal,?? with
concentrations of populations in NAP (eastern) and
GBA (western) and relatively few populations in in-
tervening areas. In addition, the apparently normal
distribution in NAP 1 CHI 1 TAM in the eastern
region masks a long-distance disjunction between
populations in northern CHI and southern TAM.
Certain recurring inconsistent distribution pat-
terns may represent vicariance events. One pattern
[found in Clarkia pulchella (58) and three Epilob-
ium?E. hornemannii (156), E. lactiflorum (157),
and E. saximontanum (169)] concerns the occur-
rence of outlier populations of western taxa (in ROC
and VAN) in the Black Hills of South Dakota in
NAP (East region). The Black Hills, home to nu-
merous disjunct montane and northern taxa (e.g.,
Asteraceae: Balsamorhiza sagittata; Pinaceae: Pi-
nus contorta, P. flexilis; Ranunculaceae: Aconitum
columbianum; Van Bruggen, 1976; Great Plains
Flora Association, 1986), have become isolated as
the climate warmed in postglacial times; the pattern
seems best explained as an example of vicariance.
Similarly, at least six taxa (Camissonia confusa [12],
three Clarkia?C. epilobioides [52], C. purpurea
[59], and C. rhomboidea [60], and two Epilobium?
E. foliosum [153] and E. glaberrimum [154]) show
strongly disjunct distributions from southern Cali-
fornia (CAL and/or VAN) to south-central Arizona
(SON), mirroring a ??trans-Sonoran Desert?? vicari-
ance event described by Axelrod (1979).
Finally, the absence of taxa from certain areas in
which they may otherwise be anticipated may rep-
resent cases of local extinction. These are, however,
difficult to prove, and in some cases clearly do not
represent extinctions. For example, some species [4
of Camissonia?C. brevipes (5), C. claviformis (11),
C. pallida (27), and C. refracta (34) and 2 of Oen-
othera?O. californica (94) and O. deltoides (98)]
otherwise widespread in the western region are
missing in ROC. Yet their absence in ROC cannot
be considered extinctions, since all of these are de-
sert taxa with southwestern distributions quite dis-
tant from the ROC boundaries. On the other hand,
many taxa with the CAL 1 VAN (17 taxa) or CAL
1 VAN 1 SON (3 taxa) distribution patterns may
have become extinct in the adjacent MOJ area,
which has become progressively more extreme in
Holocene time, and progressively inhospitable to
many species (Axelrod, 1979). The absence of
many taxa in the MOJ region may have forced MOJ
into the position as the sister group to the rest of
the western region, when it may in fact be a more
recently derived area (Van Devender & Spaulding,
1979).
The establishment of western and eastern North
American major regions found by PAE and track
compatibility analysis agrees with many previous
analyses (e.g., Li, 1952; Croizat, 1965; Graham,
1972; Iltis, 1983; Xiang et al., 1998, 2000; Wen,
Volume 91, Number 1
2004
177Katinas et al.
Geographical Diversification
1999; Guo & Ricklefs, 2000; Donoghue et al.,
2001; Sanmart??n et al., 2001). These analyses have
defined the two broad biogeographic units based on
the distributions of many taxa, some of which were
evaluated in a phylogenetic context. In many of
those analyses, however, there exists a relationship
of these areas with East Asia. Disjunct North Amer-
ican?Asian taxa have been considered as Tertiary
relics with former widespread distributions during
the Paleogene. This ??Arcto-Tertiary geoflora??
(Wolfe, 1978; Larsen, 1980) resulted from migra-
tions between eastern Asia and North America
through Beringia or across the north Atlantic. The
distributional patterns of Epilobieae, Gongylocar-
peae, and Onagreae show a close relationship be-
tween eastern and western North America, with
both areas more related to the Neotropics than to
the Palearctic, and a weak association between
northern North America and Asia. Our results do
not reject other hypotheses of such continental con-
nections. The taxa of Onagraceae chosen for our
analysis?the tribes Epilobieae, Gongylocarpeae,
and Onagreae?display a biogeographical history
that may differ from those of other taxa, but that
can coexist at the same time. Our analysis does not
disprove the migration of taxa (including Epilo-
bieae, Gongylocarpeae, and Onagreae) through the
Bering and Atlantic northern land bridges, or
through the Panama isthmus. The East and West
tracks show that two ancestral biotas existed on
both sides of North America, with the species of
each track sharing a common distributional history.
CORRELATION OF BIOGEOGRAPHIC PATTERN WITH
GEOLOGIC AND PALEOCLIMATIC EVIDENCE
The geological and climatic processes in the past
provide at least partial explanations for the current
biogeographical patterns in North America of Epi-
lobieae, Gongylocarpeae, and Onagreae. Major his-
torical events in this area include orogenic pro-
cesses such as the uplifting of the Rocky
Mountains, the Sierra Madre, and western Cordil-
lera, and the most recent glaciations (summary in
Graham, 1999).
The uplifting of the Rocky Mountains together
with the uplifting of the Sierra Madre Occidental
in the early Tertiary remarkably changed the biota
of western North America, creating a barrier for
floristic exchanges between eastern and western
North America. This had two main effects on the
flora of western North America: significant extinc-
tion of taxa because of the increasingly dry climate,
and accelerated speciation and diversification of
new taxa (Qian, 2001). Indeed, the area of the
southern Rocky Mountains and the Sierra Madre
Occidental was an important center for the evolu-
tion of the Madro-Tertiary geoflora (Axelrod, 1958).
The early diversification of Onagraceae tribe Ona-
greae was postulated to have taken place in the
Madrean vegetation of western North America (Ra-
ven & Axelrod, 1978). Until recently, tribe Gon-
gylocarpeae, also endemic to the Madrean region,
was considered to be the basal branch of Onagreae
(Carlquist & Raven, 1966). Tribe Epilobieae also
may have originated in western North America as
part of the Madro-Tertiary geoflora (Raven, 1976;
Baum et al., 1994), but evidence from fossil pollen
is equivocal, and the distribution of Chamerion and
its position as sister to Epilobium (Baum et al.,
1994) suggest a possible origin in western Eurasia
(Raven & Raven, 1976). The strong association of
Epilobium to the western track, and the endemism
of the near-basal species E. rigidum (Baum et al.,
1994; Levin et al., 2004) in the VAN region, sup-
port an origin of the genus in western North Amer-
ica. The Madro-Tertiary geoflora had already ap-
peared on the drier borders of the North American
tropics by the Middle Eocene, and probably occu-
pied much of the southwestern United States and
adjacent Mexico by the close of the Oligocene. It
extended its range in all directions in response to
the expanding aridity in the succeeding Miocene
epoch (Axelrod, 1958; Valliente-Banuet et al.,
1998). Major expansion of Onagraceae tribes On-
agreae, Gongylocarpeae, and Epilobieae may have
occurred during the Miocene and Pliocene (Raven
& Axelrod, 1974; Raven & Raven, 1976; Raven,
1979).
From the late Oligocene (25 mya) through the
Pliocene, new orogeny gave rise to the present
western Cordilleran System, including major defor-
mation and uplift of the Rocky Mountains, Sierra
Nevada, Sierra Madre Occidental, and Sierra Ma-
dre Oriental (Axelrod & Raven, 1985; Wing, 1987;
Graham, 1993). This resulted in cooler and drier
climates that precipitated the development of grass-
lands in central North America (Sanmart??n et al.,
2001), being thus a third event differentiating the
western and the eastern floras. However, Wen
(1999) noted that the close biogeographic relation-
ship between western and eastern North America
suggests that the Cordilleran range was not an ef-
fective barrier to exchange between these two flo-
ristic regions.
In the Quaternary period, the flora of North
America experienced late Pleistocene full-glacial
conditions (20,000?15,000 yr. b.p.), late-glacial cli-
matic amelioration (15,000?10,000 yr. b.p.), and
Holocene interglacial conditions of the last 10,000
178 Annals of the
Missouri Botanical Garden
years (Graham, 1999). The Quaternary can be char-
acterized more by changes in the distributions of
plant taxa than by the evolution of new genera and
species (Delcourt & Delcourt, 1993). During times
of glacial maxima, fragmented populations may
have undergone genetic differentiation within iso-
lated refugia. With the onset of interglacial condi-
tions, migration and expansion of distributional
ranges would reestablish genetic exchanges be-
tween populations within species and among close-
ly related species that were formerly isolated. Gri-
chuk (1984) proposed the term ??migration flora?? to
denote floras that moved into a given region after
the preceding flora was eliminated by glacial or
periglacial conditions. Delcourt and Delcourt
(1993) suggested that the individual elements of
such migration floras could move hundred to thou-
sands of kilometers as they differentially responded
to changing climatic and competitive conditions.
Different groups and species of Onagraceae tribes
Epilobieae, Gongylocarpeae, and Onagreae appear
to have participated in such Quaternary migrations
into western and eastern North America, apparently
from areas in the southwestern part of the conti-
nent. We hope that this scenario may be tested us-
ing other groups of plants and animals, as well as
other analytical tools including phylogenetic meth-
ods.
Literature Cited
Aiken, S. G., M. J. Dallwitz, L. L. Consaul, C. L. Mc-
Jannet, L. J. Gillespie, R. L. Boles, G. W. Argus, J. M.
Gillett, P. J. Scott, R. Elven, M. C. LeBlanc, A. K.
Brysting & H. Solstad. 1999 onward. Flora of the Ca-
nadian Arctic Archipelago: Descriptions, Illustrations,
Identification, and Information Retrieval. Version: 29th
April 2003. ^http://www.mun.ca/biology/delta/arcticf/&.
Axelrod, D. I. 1958. Evolution of the Madro-Tertiary geo-
flora. Bot. Rev. 24: 433?509.
. 1979. Age and origin of Sonoran desert vegeta-
tion. Occas. Pap. Calif. Acad. Sci. 132: 1?74.
& P. H. Raven. 1985. Origins of the Cordilleran
flora. J. Biogeogr. 12: 21?47.
Ayala, R., T. L. Griswold & S. H. Bullock. 1993. The
native bees of Mexico. Pp. 179?131 in T. P. Rama-
moorthy, R. Bye, A. Lot & J. Fa (editors), Biological
Diversity of Mexico: Origins and Distribution. Oxford
Univ. Press, New York, Oxford.
Barbour, M. G. & N. L. Christensen. 1993. Vegetation.
Pp. 97?131 in Flora of North America, North of Mexico,
Vol. 1. Oxford Univ. Press, Oxford, New York.
Baum, D. A., K. J. Sytsma & P. C. Hoch. 1994. A phy-
logenetic analysis of Epilobium (Onagraceae) based on
nuclear ribosomal DNA sequences. Syst. Bot. 19: 363?
388.
Berry, E. W. 1930. Revision of the Lower Eocene Wilcox
flora of the southeastern states. U.S. Geol. Surv. Prof.
Paper 156.
Boufford, D. E. 1982 [1983]. The systematics and evolu-
tion of Circaea (Onagraceae). Ann. Missouri Bot. Gard.
69: 804?994.
Brooks, D. R., M. G. P. van Veller & D. A. McLennan.
2001. How to do BPA, really. J. Biogeogr. 28: 345?358.
Brown, D. E., C. H. Lowe & C. P. Pase. 1979. A digitized
classification system for the biotic communities of North
America, with community (series) and association ex-
amples for the southwest. J. Ariz.-Nev. Acad. Sci. 14
(Suppl. 1): 1?16.
, F. Reichenbacher & S. E. Franson. 1998. A clas-
sification of North American biotic communities. Univ.
Utah Press, Salt Lake City.
California Academy of Sciences. 2003. Entomology. World
Wide Web site: ^www.calacademy.org/research/entomology/&.
Carlquist, S. & P. H. Raven. 1966. The systematics and
anatomy of Gongylocarpus (Onagraceae). Amer. J. Bot.
53: 378?390.
Chen, C. J., P. C. Hoch & P. H. Raven. 1992. Systematics
of Epilobium (Onagraceae) in China. Syst. Bot. Monogr.
34: 1?209.
Connor, E. F. 1988. Fossils, phenetics and phylogenetics:
Inferring the historical dynamics of biogeographic dis-
tributions. Pp. 254?269 in J. K. Liebherr (editor), Zoo-
geography of Caribbean Insects. Cornell Univ. Press,
Ithaca.
Correll, D. S. & M. C. Johnston. 1970. Manual of the
Vascular Plants of Texas. Texas Research Foundation,
Renner, Texas.
Cracraft, J. 1991. Patterns of diversification within conti-
nental biotas: Hierarchical congruence among the areas
of endemism of Australian vertebrates. Austral. Syst.
Bot. 4: 211?427.
Craw, R. C. 1988. Continuing the synthesis between pan-
biogeography, phylogenetic systematics and geology as
illustrated by empirical studies on the biogeography of
New Zealand and the Chatham Islands. Syst. Zool. 37:
291?310.
. 1989. Quantitative panbiogeography: Introduc-
tion to methods. New Zealand J. Zool. 16: 485?494.
. 1990. New Zealand biogeography: A panbiogeo-
graphic approach. New Zealand J. Zool. 16: 527?547.
, J. R. Grehan & M. J. Heads. 1999. Panbiogeog-
raphy: Tracking the history of life. Oxford Biogeography
series n. 11. Oxford Univ. Press, New York, Oxford.
Crisci, J. V. 2001. The voice of historical biogeography. J.
Biogeogr. 28: 157?168.
, L. Katinas & P. Posadas. 2000. Introduccio?n a
la teor??a y pra?ctica de la biogeograf??a histo?rica. Socie-
dad Argentina de Bota?nica, Buenos Aires, Argentina.
, & . 2003. Historical Biogeogra-
phy: An Introduction. Harvard Univ. Press, Cambridge,
Massachusetts.
Croizat, L. 1958. Panbiogeography, Vols. I, IIa, and IIb.
Published by the author, Caracas, Venezuela.
. 1965. On approaching the subgeneric classifi-
cation of Euphorbia paplidion and E. tetrapora. SouthW.
Naturalist 10: 241?247.
. 1981. Biogeography: Past, present, and future.
Pp. 501?523 in G. Nelson & D. E. Rosen (editors),
Vicariance Biogeography: A Critique. Columbia Univ.
Press, New York.
Delcourt, P. A. & H. R. Delcourt. 1993. Paleoclimates,
paleovegetation, and paleofloras during the late Quater-
nary. Pp. 71?94 in Flora of North America, North of
Mexico, Vol. 1. Oxford Univ. Press, Oxford, New York.
Dice, L. R. 1943. The Biotic Provinces of North America.
Univ. Michigan Press, Ann Arbor.
Volume 91, Number 1
2004
179Katinas et al.
Geographical Diversification
Dietrich, W. & W. L. Wagner. 1988. Systematics of Oen-
othera section Oenothera subsection Raimannia and
subsection Nutantigemma. Syst. Bot. Monogr. 24: 1?91.
, P. H. Raven & W. L. Wagner. 1985. Revision of
Oenothera sect. Oenothera subsect. Emersonia (Onagra-
ceae). Syst. Bot. 10: 29?48.
, W. L. Wagner & P. H. Raven. 1997. Systematics
of Oenothera section Oenothera subsection Oenothera
(Onagraceae). Syst. Bot. Monogr. 50: 1?234.
Donoghue, M. J., C. D. Bell & J. Li. 2001. Phylogenetic
patterns in northern hemisphere plant geography. Int. J.
Plant. Sci. 162 (6 Suppl.): S41?S52.
Escalante Pliego, P., A. G. Navarro Sigu?enza & A. Town-
send Peterson. 1993. A geographic, ecological, and his-
torical analysis of land bird diversity in Mexico. Pp.
281?307 in T. P. Ramamoorthy, R. Bye, A. Lot & J. Fa
(editors), Biological Diversity of Mexico: Origins and
Distribution. Oxford Univ. Press, New York, Oxford.
Fa, J. E. & L. M. Morales. 1993. Patterns of mammalian
diversity in Mexico. Pp. 319?361 in T. P. Ramamoorthy,
R. Bye, A. Lot & J. Fa (editors), Biological Diversity of
Mexico: Origins and Distribution. Oxford Univ. Press,
New York, Oxford.
Felsenstein, J. 1985. Confidence limits on phylogenies:
An approach using the bootstrap. Evolution 39: 783?
791.
Froese, R. & D. Pauly (editors). 2003. FishBase. Version:
12 November 2003. ^www.fishbase.org&.
Frost, D. R. 2002. Amphibian Species of the World: An
Online Reference. V2.21 (15 July 2002). ^http://
research.amnh.org/herpetology/amphibia/index.html&.
Graham, A. 1972. Outline of the origin and historical rec-
ognition of floristic affinities between Asia and eastern
North America. Pp. 1?18 in A. Graham (editor), Flo-
ristics and Paleofloristics of Asia and Eastern North
America. Elsevier, New York.
. 1993. History of the vegetation: Cretaceous
(Maastrichtian)?Tertiary. Pp. 57?70 in Flora of North
America, North of Mexico, Vol. 1. Oxford Univ. Press,
New York, Oxford.
. 1999. Late Cretaceous and Cenozoic History of
North American Vegetation (North of Mexico). Oxford
Univ. Press, Oxford.
Great Plains Flora Association. 1986. Flora of the Great
Plains. Univ. Press Kansas, Lawrence.
Grehan, J. R. 1988a. Panbiogeography: Evolution in space
and time. Riv. Biol., Biol. Forum 81: 469?498.
. 1988b. Biogeographic homology: Ratites and the
southern beeches. Riv. Biol., Biol. Forum 81: 577?587.
Grichuk, V. P. 1984. Late Pleistocene vegetation history.
Pp. 155?178 in A. A. Velichko (editor); H. E. Wright
& C. W. Barnosky (editors, English ed.), Late Quater-
nary Environments of the Soviet Union. Univ. Minnesota
Press, Minneapolis.
Guo, Q. & R. E. Ricklefs. 2000. Species richness in plant
genera disjunct between temperate eastern Asia and
North America. Bot. J. Linn. Soc. 134: 401?423.
Henderson, I. 1990. Quantitative biogeography: An inves-
tigation into concepts and methods. New Zealand J.
Zool. 16: 495?510.
. 1991. Biogeography without areas? Austral. Syst.
Bot. 4: 59?71.
Hickman, J. C. (editor). 1993. The Jepson Manual: Higher
Plants of California. Univ. California Press, Berkeley
and Los Angeles.
Hoch, P. C. 1986. Epilobium. Pp. 504?509 in Flora of the
Great Plains. Univ. Press Kansas, Lawrence.
. 1993. Epilobium. Pp. 793?798 in J. C. Hickman
(editor), The Jepson Manual: Higher Plants of Califor-
nia. Univ. California Press, Berkeley and Los Angeles.
, J. V. Crisci, H. Tobe & P. E. Berry. 1993. A
cladistic analysis of the plant family Onagraceae. Syst.
Bot. 18: 31?47.
Iltis, H. H. 1983. Biogeographical relationships between
temperate eastern Asia and temperate eastern North
America. Pp. 49?51 in Proceedings of U.S.?Japan Sci-
entific Seminar on the Origin of the Eastern Asian and
North American Floras from Arctotertiary Precursors.
U.S.?Japan Cooperative Science Program, New York.
Larsen, J. A. 1980. The Boreal Ecosystem. Academic
Press, New York.
Lepage, D. 2003 AviBase. ^www.bsc-eoc.org/avibase&.
Levin, R. A., W. L. Wagner, P. C. Hoch, M. Nepokroeff,
J. C. Pires, E. A. Zimmer & K. J. Sytsma. 2003. Family-
level relationships of Onagraceae based on chloroplast
rbcL and ndhF data. Amer. J. Bot. 90: 107?115.
, , , W. J. Hahn, A. Rodriguez, D.
A. Baum, L. Katinas, E. A. Zimmer & K. J. Sytsma.
2004. Paraphyly in tribe Onagreae: Insights into phy-
logenetic relationships of Onagraceae based on nuclear
and chloroplast sequence data. Syst. Bot. 29: 147?164.
Lewis, H. 1993. Clarkia. Pp. 786?793 in J. C. Hickman
(editor), The Jepson Manual: Higher Plants of Califor-
nia. Univ. California Press, Berkeley and Los Angeles.
& M. E. Lewis. 1955. The genus Clarkia. Univ.
Calif. Publ. Bot. 20: 241?392.
& J. Szweykowski. 1964. The genus Gayophytym
(Onagraceae). Brittonia 16: 343?391.
Li, H. 1952. Floristic relationships between eastern Asia
and eastern North America. Trans. Amer. Philos. Soc.
42: 371?429.
Li, S. & K. T. Adair. 1994. Species pools in eastern Asia
and North America. Sida 16: 281?299.
Liebherr, J. K. 1991a. Phylogeny and revision of the An-
chomenus clade: The genera Tetraleucus, Anchomenus,
Sericoda, and Elliptoleus (Coleoptera: Carabidae: Pla-
tynini). Bull. Amer. Mus. Nat. Hist. 202: 1?163.
. 1991b. A general area cladogram for montane
Mexico based on distributions in the Platynine genera
Elliptoleus and Calathus (Coleoptera: Carabidae). Proc.
Entomol. Soc. Wash. 93: 390?406.
. 1992. Phylogeny and revision of the Platynus
degallieri species group (Coleoptera: Carabida: Platyn-
ini). Bull. Amer. Mus. Nat. Hist. 214: 1?115.
. 1994a. Identification of New World Agonum, re-
view of the Mexican fauna, and description of Incagon-
um, new genus, from South America (Coleoptera: Car-
abidae: Platynini). J. Entomol. Soc. 102: 1?55.
. 1994b. Biogeographic patterns of montane Mex-
ican and Central American Carabidae (Coleoptera).
Canad. Entomol. 126: 841?860.
Llorente-Bousquets, J. & A. Luis-Mart??nez. 1993. Con-
servation-oriented analysis of Mexican butterflies: Pap-
ilionidae (Lepidoptera, Papilionoidea). Pp. 147?178 in
T. P. Ramamoorthy, R. Bye, A. Lot & J. Fa (editors),
Biological Diversity of Mexico: Origins and Distribu-
tion. Oxford Univ. Press, New York, Oxford.
MacMahon, J. A. 2000. Warm deserts. Pp. 285?322 in M.
G. Barbour & W. D. Billings (editors), North American
Terrestrial Vegetation. Cambridge Univ. Press, Cam-
bridge.
Maddison, D. R. & W. P. Maddison. 2000. MacClade 4:
Analysis of Phylogeny and Character Evolution. Vers.
4.0. Sinauer, Sunderland, Massachusetts.
180 Annals of the
Missouri Botanical Garden
Marshall, C. J. & J. K. Liebherr. 2000. Cladistic bioge-
ography of the Mexican transition zone. J. Biogeogr. 27:
203?216.
McAllister, D. E., S. P. Platania, F. W. Schueler, M. E.
Baldwin & D. S. Lee. 1986. Ichthyofaunal patterns on
a geographic grid. Pp. 17?51 in C. H. Hocutt & E. O.
Wiley (editors), The Zoogeography of North American
Freshwater Fishes. John Wiley & Sons, New York.
McLaughlin, S. P. 1989. Natural floristic areas of the west-
ern United States. J. Biogeogr. 16: 239?248.
. 1992. Are floristic areas hierarchically arranged?
J. Biogeogr. 19: 21?32.
Meacham, C. 1984. Evaluating characters by character
compatibility analysis. Pp. 152?165 in T. Duncan & T.
F. Stuessy (editors), Cladistic: Perspectives on the Re-
construction of the Evolutionary History. Columbia
Univ. Press, New York.
Miranda, F. & A. J. Sharp. 1950. Characteristics of the
vegetation in certain temperate regions of eastern Mex-
ico. Ecology 31: 313?333.
Morrone, J. J. 2001. Toward a cladistic model for the Ca-
ribbean subregion: Delimitation of areas of endemism.
Caldasia 23: 43?76.
& J. V. Crisci. 1990. Pangiogeograf??a: Fundamen-
tos y me?todos. Evolucio?n Biolo?gica (Bogota?) 4: 119?
140.
& . 1995. Historical biogeography: Intro-
duction to methods. Ann. Rev. Ecol. Syst. 26: 373?401.
, D. Espinosa Organista, C. Aguilar Zun?iga & J.
Llorente Bousquets. 1999. Preliminary classification of
the Mexican biogeographic provinces: A parsimony
analysis of endemicity based on plant, insect, and bird
taxa. SouthW. Naturalist 44: 507?544.
Mosquin, T. 1966. A new taxonomy for Epilobium angus-
tifolium L. (Onagraceae). Brittonia 18: 167?188.
Nowak, R. M. 1997. Walker?s Mammals of the World.
Johns Hopkins Univ. Press. ^www.press.jhu.edu/books/
walkerspmammalspofpthepworld/&.
Page, R. D. M. 1987. Graphs and generalized tracks:
Quantifying Croizat?s panbiogeography. Syst. Zool. 36:
1?17.
Platnick, N. I. 1991. On areas of endemism. Austral. Syst.
Bot. 4 [Commentary].
Qian, H. 2001. Floristic analysis of vascular plant genera
of North America north of Mexico: Spatial patterning of
phytogeography. J. Biogeogr. 28: 525?534.
Ramamoorthy, T. P., R. Bye, A. Lot & J. Fa. 1993. Bio-
logical Diversity of Mexico: Origins and Distribution.
Oxford Univ. Press, New York, Oxford.
Raven, P. H. 1962. Systematics of Oenothera subgenus
Chylismia. Univ. Calif. Publ. Bot. 34: 1?122.
. 1969. A revision of the genus Camissonia (On-
agraceae). Contr. U.S. Natl. Herb. 37: 161?396.
. 1976. Generic and sectional delimitation in On-
agraceae, tribe Epilobieae. Ann. Missouri Bot. Gard.
63: 326?340.
. 1979. A survey of reproductive biology in Ona-
graceae. New Zealand J. Bot. 17: 575?593.
. 1988. Onagraceae as a model of plant evolution.
Pp. 85?107 in L. D. Gottlieb & S. K. Jain (editors),
Plant Evolutionary Biology. Chapman & Hall, London
and New York.
& D. I. Axelrod. 1974. Angiosperm biogeography
and past continental movements. Ann. Missouri Bot.
Gard. 61: 539?673.
& . 1978. Origin and relationships of the
California flora. Univ. Calif. Publ. Bot. 72: 1?134.
& D. P. Gregory. 1972. A revision of the genus
Gaura (Onagraceae). Mem. Torrey Bot. Club 23: 1?96.
& D. M. Moore. 1965. A revision of Boisduvalia
(Onagraceae). Brittonia 17: 238?254.
& T. E. Raven. 1976. The genus Epilobium (On-
agraceae) in Australasia: A systematic and evolutionary
study. New Zealand Dept. Sci. Industr. Res. Bull. 216:
1?321.
Ricketts, T. H., E. Dinerstein, D. M. Olson, C. J. Loucks,
W. Eichbaum, D. DellaSala, K. Kavanagh, P. Hedao, P.
T. Hurley, K. M. Carney, R. Abell & S. Walters. 1999.
Terrestrial Ecoregions of North America: A Conserva-
tion Assessment. Island Press, Washington, D.C.
Rosen, B. R. 1988. From fossils to earth history: Applied
historical biogeography. Pp. 437?481 in A. A. Myers &
P. S. Giller (editors), Analytical Biogeography: An In-
tegrated Approach to the Study of Animal and Plant
Distributions. Chapman & Hall, New York.
& A. B. Smith. 1988. Tectonics from fossils?
Analysis of reef-coral and sea-urchin distributions from
Late Cretaceous to Recent, using a new method. Pp.
275?306 in M. G. Audley-Charles & A. Hallam (edi-
tors), Gondwana and Tethys. Oxford Univ. Press, Ox-
ford.
Rzedowski, J. 1978. Vegetacio?n de Me?xico. Editorial Li-
musa, D. F., Me?xico.
Salisbury, B. A. 1999. SECANT: Strongest Evidence Com-
patibility Analytical Tool. Vers. 2.2. Department of
Ecology & Evolutionary Biology, Yale University, New
Haven.
Sanmart??n, I., H. Enghoff & F. Ronquist. 2001. Patterns
of animal dispersal, vicariance and diversification in the
Holarctic. Biol. J. Linn. Soc. 73: 345?390.
Small, E. 1968. The systematics of autopolyploidy in Epi-
lobium latifolium (Onagraceae). Brittonia: 169?181.
Straley, G. B. 1977 [1978]. Systematics of Oenothera sect.
Kneiffia (Onagraceae). Ann. Missouri Bot. Gard. 64:
381?424.
Swofford, D. L. 2001. PAUP*: Phylogenetic Analysis Us-
ing Parsimony. Vers. 4.0b10. Sinauer, Sunderland, Mas-
sachusetts.
Takhtajan, D. H. 1986. Floristic Regions of the World.
Univ. California Press, Berkeley.
Thorne, R. F. 1993. Phytogeography. Pp. 132?153 in Flora
of North America, North of Mexico. Oxford Univ. Press,
New York, Oxford.
Towner, H. F. 1977. The biosystematics of Calylophus
(Onagraceae). Ann. Missouri Bot. Gard. 64: 48?120.
Uetz, P., R. Chenna, T. Etzold & J. Hallermann. 2003.
The EMBL Reptile Database. ^www.reptile-database.
org&.
Valliente-Banuet, A., N. Flores Hernandez, M. Verdu &
P. Davila. 1998. The chaparral vegetation in Mexico
under non-Mediterranean climate: The convergence and
Madrean-Tethyan hypotheses reconsidered. Amer. J.
Bot. 85: 1398?1408.
Van Bruggen, T. 1976. The Vascular Plants of South Da-
kota. Iowa State Univ. Press, Ames.
Van Deventer, T. R. & W. G. Spaulding. 1979. Develop-
ment of vegetation and climate in the southwestern
United States. Science 204: 701?710.
Wagner, W. L. 1984 [1985]. Reconsideration of Oenothera
subg. Gauropsis (Onagraceae). Ann. Missouri Bot. Gard.
71: 1114?1127.
. 1986. New taxa in Oenothera (Onagraceae). Ann.
Missouri Bot. Gard. 73: 475?480.
. 1993. Onagraceae. Pp. 776?804 in J. C. Hick-
Volume 91, Number 1
2004
181Katinas et al.
Geographical Diversification
man (editor), The Jepson Manual: Higher Plants of Cal-
ifornia. Univ. California Press, Berkeley and Los An-
geles.
. 2004. Resolving a nomenclatural and taxonomic
problem in Mexican Oenothera sect. Hartmannia (tribe
Onagreae, Onagraceae). Novon 14: 124?133.
, R. E. Stockhouse & W. M. Klein. 1985. The sys-
tematics and evolution of the Oenothera caespitosa com-
plex (Onagraceae). Monogr. Syst. Bot. Missouri Bot.
Gard. 12: 1?103.
Wen, J. 1999. Evolution of eastern Asian and eastern
North American disjunct distributions in flowering
plants. Ann. Rev. Ecol. Syst. 30: 421?455.
Wilson, D. E. & D. M. Reeder (editors). 1993. Mammal
Species of the World. Smithsonian Institution Press.
^www.nmnh.si.edu/msw/&.
Wing, S. L. 1987. Eocene and Oligocene floras and veg-
etation of the Rocky Mountains. Ann. Missouri Bot.
Gard. 74: 748?784.
Wolfe, J. A. 1978. A paleobotanical interpretation of Ter-
tiary climates in the Northern Hemisphere. Amer. Sci.
66: 694?703.
Xiang, Q. Y., D. E. Soltis & P. S. Soltis. 1998. The eastern
Asian and eastern and western North America floristic
disjunction: Congruent phylogenetic patterns in seven
diverse genera. Molec. Phylogenet. Evol. 10: 178?190.
, , , S. R. Manchester & D. J. Craw-
ford. 2000. Timing the Eastern Asian?Eastern North
American floristic disjunction: Molecular clock corrob-
orates paleontological estimates. Molec. Phylogenet.
Evol. 15: 462?472.
APPENDIX 1.
North American areas of endemism used in this analysis;
see text for sources and explanation. References for plant
endemics generally follow Takhtajan (1986); these are sup-
plemented in some areas by Barbour & Christensen (1993),
in Canada by Aiken et al. (1999: ^www.mun.ca/biology/
delta/arcticf/&); in California by Hickman (1993), and in
Mexico by Rzedowski (1978) and Ramamoorthy et al.
(1993). Names were checked against the on-line Flora of
North America database (^http://hua.huh.harvard.edu/
FNA&). Endemic animals are arranged in the following or-
der: fish, amphibians, reptiles, birds, mammals, inverte-
brates; within groups, alphabetical by family. References for
animal endemics are as follows: 1Ricketts et al. (1999);
2Mammals of the World (Wilson & Reeder, 1993:
^www.nmnh.si.edu/msw/&); 3Avibase (Lepage, 2003: ^www.
bsc-eoc.org/avibase&); 4Amphibian Species of the World
(Frost, 2002: ^research.amnh.org/herpetology/amphibia/&);
5Walker?s Mammals of the World (Nowak, 1997: ^www.
press.jhu.edu/books/walkerspmammalspofpthepworld/&);
6Fishbase (Froese & Pauly, 2003: ^www.fishbase.org&); 7Rep-
tile database (Uetz et al., 2003: ^www.reptile-database.
org&); 8entomology (California Academy of Sciences, 2003:
^www.calacademy.org/research/entomology&).
1. Arctic (ARC): includes most of coastal Alaska, north-
ern coastal Canada, all of the ice-free Canadian Ar-
chipelago, and Greenland. The flora is depauperate
in a nearly tree-less region of tundra and polar desert,
with fewer than 1000 species of vascular plants. En-
demism at the species level is moderate (Aiken et al.,
1999), e.g.: Asteraceae: Taraxacum hyparcticum;
Brassicaceae: Braya thorild-wulffii, Parrya arctica;
Caryophyllaceae: Cerastium regelii, Silene sorensenis;
Orobanchaceae: Castilleja arctica; Polemoniaceae:
Phlox richardsonii. Endemic fauna include Mammals
[Cervidae] Rangifer tarandus pearyi (Peary caribou)1,5;
[Leporidae] Lepus arcticus (arctic hare)1,2; [Soricidae]
Sorex pribilofensis (Pribiloff Island shrew)1,5.
2. Canadian (CAN): forms a broad band across Canada
and Alaska, south of ARC and north of Rocky Moun-
tain (ROC) and Appalachian (APP) regions, including
extreme northern New England, Michigan, and Min-
nesota. Consists primarily of taiga and coniferous bo-
real forests, with dominant tree species in Abies, Bet-
ula, Larix, Picea, Pinus, and Populus. Some endemic
plants include Asteraceae: Aster yukonensis; Boragi-
naceae: Cryptantha shakletteana; Brassicaceae: Erys-
imum aspermum; Caryophyllaceae: Silene williamsii;
Fabaceae: Astragalus ecosmus; Orobanchaceae: Cas-
tilleja annua; Polygonaceae: Eriogonum flavum; Por-
tulacaceae: Claytonia bostockii; Primulaceae: Doug-
lasia gormanii. Endemic fauna include Mammals:
[Soricidae] Sorex gaspensis (Gaspe shrew)2,5; Insects:
[Lepidoptera] Coenonympha nepisiquit (maritime ring-
let butterfly)1.
3. Appalachian (APP): includes a small part of southern
Ontario and Quebec, Canada, and most of the eastern
United States, excluding the Atlantic and Gulf Coast-
al region (ATL) to the south. Extends from central
Maine, southern Canada, and Minnesota to central
Georgia, central Alabama, the Ozark Plateau and the
Quachita Mts. in Missouri and Arkansas, and eastern
Texas. In Texas, corresponds to the ??Post Oak Savan-
nah?? and ??Blackland Prairies?? areas of Correll and
Johnston (1970). Dominant climax vegetation is the
eastern deciduous forest, with dominant tree species
in Acer, Aesculus, Betula, Fagus, Magnolia, Quercus,
and Tilia. Many endemic plant species, including
Magnoliaceae: Magnolia fraseri; Menispermaceae:
Menispermum canadense; Pinaceae: Abies fraseri;
Ranunculaceae: Aconitum reclinatum, Anemone acu-
tiloba; Rosaceae: Prunus alleghanensis; Ulmaceae:
Ulmus serotina. Endemic fauna include Amphibians:
[Plethodontidae] Desmognathus welten (Black Moun-
tain salamander)1,4; Reptiles: [Emydidae] Clemmys
muhlenbergii (bog turtle)1; Birds: [Emberizidae] Den-
droica kirtlandii (Kirkland?s warbler)1,3; Annelids:
[Acanthodrilidae] Diplocardia meansi (earthworm)1.
4. Atlantic and Gulf Coastal (ATL): occupies the geolog-
ic coastal plain of the Atlantic and Gulf Coast states
of the United States, from Massachusetts and New
Jersey to Florida and west to south-central Texas. In
Texas, corresponds to the ??Pineywoods?? and ??Gulf
Prairies and Marshes?? areas of Correll and Johnston
(1970). Also extends across the lower Mississippi
River valley to southern Missouri and Illinois. Much
of the coastal plain is characterized by extensive for-
ests of Pinus, replaced in some areas by Carya, Fa-
gus, and/or Quercus, and in wetter areas by Taxodium
distichum and species of Nyssa and Fraxinus. Endem-
ic taxa include Onagraceae (tribe Jussiaeeae): Lud-
wigia lanceolata, L. pilosa, L. ravenii, and L. suffru-
ticosa, and several hundred species including
Annonaceae: Asimina incana; Iridaceae: Iris hexago-
na; Lauraceae: Persea palustris; Pinaceae: Pinus el-
liottii; Salicaceae: Salix floridana; Simaroubaceae:
Leitneria floridana; Taxaceae: Taxus floridana, Torre-
ya taxifolia. Endemic fauna include Reptiles [Testu-
dinidae] Gopherus polyphemus (gopher tortoise)1;
Birds: [Corvidae] Aphelocoma coerulescens coerules-
cens (Florida scrub jay)1,3; [Picidae] Picoides borealis
182 Annals of the
Missouri Botanical Garden
(red-cockaded woodpecker)1,3; Mammals: [Ursidae]
Ursus americanus floridanus (Florida black bear)5.
5. North American Prairies (NAP): includes prairies and
plains between the eastern deciduous forest of APP
on the east, the coniferous forests of ROC on the west
and CAN on the north, and the arid semi-deserts of
CHI and TAM to the southwest. Corresponds for the
most part with the ??Great Plains?? (Great Plains Flora
Assoc., 1986), but in Texas also includes the ??Ed-
wards Plateau,?? ??Rolling Plains,?? and ??High Plains??
areas of Correll and Johnston (1970). Grasses are
dominant in this region, with a rich mix of perennial
forbs, and forest trees in some areas near rivers. No
endemic families, few endemic genera, and some en-
demic species, including the bryophyte Pottiaceae:
Aschisma kansanum; and Agavaceae: Yucca rupicola;
Brassicaceae: Lesquerella angustifolia; Fabaceae: As-
tragalus gracilis, Psoralea cuspidata; Polygonaceae:
Eriogonum correllii; Valerianaceae: Valeriana texana.
Endemic fauna include Amphibians: [Plethodontidae]
Typhlomolge (Eurycea) rathbuni (Texas blind sala-
mander)1,4 and T. robusta (Blanco blind salamander)1,4;
Birds: [Phasianidae] Tympanuchus cupido (greater
prairie chicken)1,3; Mammals: [Canidae] Vulpes velox
(swift fox)1,2.
6. Vancouverian (VAN): extends as a coastal strip from
Kodiak Island in Alaska to coastal British Columbia,
widening in Washington and Oregon to include the
Cascade, Olympic, and Coast Ranges, extending into
California through the Klamath and Northern Coast
ranges in the west and through the southern Cascades
into the Sierra Nevada to its terminus in southern
California. In California, VAN corresponds to the NW,
CW, CaR, and SN regions of The Jepson Manual
(Hickman, 1993). Conifers dominate the climax veg-
etation, along with some broad-leaved species of Acer,
Alnus, Cornus, Fraxinus, Populus, and Quercus. There
are endemic genera and some 500 to 600 endemic
species, including Apiaceae: Lomatium bradshawii;
Asteraceae: Aster paludicola, Erigeron cervinus, Se-
necio clarkianus; Iridaceae: Iris bracteata; Sarraceni-
aceae: Darlingtonia californica; Taxodiaceae: Sequoia
sempervirens, Sequoiadendron giganteum. Endemic
fauna include Fishes: [Catostomidae] Catostomus rim-
iculus (Jenny Creek sucker)1,6; [Cyprinidae] Gila bi-
color bicolor (Tui chub)1,6; Amphibians: [Dicampto-
dontidae] Dicamptodon ensatus (Pacific giant
salamander)1,4; Birds: [Strigidae] Strix occidentalis
caurina (northern spotted owl)1,3; Insects: [Lepidop-
tera] Colias behrii (Sierra sulfur butterfly)1.
7. Rocky Mountain (ROC): includes the Rocky Moun-
tains and associated inland ranges from northern Brit-
ish Columbia and southwestern Yukon to central
Oregon, south-central Idaho, extreme northeastern
Utah, and north-central New Mexico, bounded on the
west by VAN and GBA and on the east by CAN and
NAP. In the extreme south, ROC borders the deserts
of CHI. Also includes some associated outlier ranges,
especially extending to the east and south of the main
cordillera. Vegetation is zoned vertically, with Pinus
ponderosa dominant in the lowest zones, and species
of Abies, Juniperus, Picea, Pinus, Populus, and Pseu-
dotsuga dominant at higher zones. Some endemic
plant species include Apiaceae: Angelica ampla,
Lomatium tuberosum; Brassicaceae: Draba grayana;
Fabaceae: Astragalus arrectus; Orobanchaceae: Cas-
tilleja christii; Plantaginaceae: Penstemon elegantulus;
Polemoniaceae: Phlox colubrina. Endemic fauna in-
clude Fishes: [Cyprinidae] Gila cypha (humpback
chub)1,6; [Salmonidae] Oncorhynchus clarki lewisi
(westslope cutthroat trout)1,6; Mammals: [Mustelidae]
Mustela negripes (black-footed ferret)1,2,5; [Sciuridae]
Cynomys leucurus (white-tailed prairie dog)1,2.
8. Great Basin (GBA): bounded on the west by the Cas-
cade-Sierra Nevada axis (VAN), on the east by ROC,
and on the south by the desert regions of MOJ, SON,
and CHI. In California, the boundaries correspond to
those of the MP and SNE (including the White and
Inyo Mountains) regions of The Jepson Manual (Hick-
man, 1993). Includes the Snake River Plains of
southern Idaho and most of the Colorado Plateau, and
consists of many north-south trending mountain rang-
es separated by broad, alkaline basins without exter-
nal drainage, with much of the area above 1300 m.
Characterized by diversity of species of Artemisia,
Chenopodiaceae, and at higher elevations by some
combination of species of Acer, Populus, Quercus,
Juniperus, and Pinus. The region has numerous en-
demic species, including Asteraceae: Chaetadelpha
wheeleri, Erigeron mancus; Loasaceae: Mentzelia
packardiae; Papaveraceae: Canbya aurea; Plantagi-
naceae: Penstemon compactus; Primulaceae: Primula
maguirei. Endemic fauna include Fishes: [Cyprini-
dae] Ptychocheilus lucius (Colorado pikeminnow)1,6;
Mammals [Heteromyidae] Microdipodops pallidus
(pale kangaroo mouse)1,2.
9. Californian (CAL): occupies a large part of the state
of California, including the Central Valley, the Coast
Ranges from the San Francisco region south into
northwestern Baja California Norte, Mexico, and the
Transverse Ranges of southern California. Bounded
on the northwest, north, and east by VAN, and on the
southeast by MOJ and SON (Raven & Axelrod, 1978).
Corresponds to the GV, CW, and SW regions of The
Jepson Manual (Hickman, 1993). The vegetation
varies altitudinally, from treeless grassland in lower
areas to chapparal and mixed forests of Aesculus, Pla-
tanus, Populus, Quercus, Salix, and conifers at higher
levels. Numerous endemic plant genera and species
include Asteraceae: Erigeron sanctarum; Fagaceae:
Quercus douglasii; Ophioglossaceae: Ophioglossum
californicum; Papaveraceae: the genus Romneya; Po-
lygonaceae: the genus Hollisteria. Endemic fauna in-
clude Fishes: [Cyprinidae] Gilia bicolor mojavensis
(Mohave Tui chub)1,6; Reptiles: [Colubridae] Masti-
cophis flagellum ruddocki (San Joaquin whipsnake)1,7;
Mammals: [Canidae] Urocyon littoralis (Island gray
fox)1,2; [Heteromyidae] Dipodomys ingens (giant kan-
garoo rat)1,2, D. venustus (narrow-faced kangaroo
rat)1,2; Perognathus inornatus (San Joaquin pocket
mouse)1,2; Insects [Lepidoptera, Pieridae] Euphydryas
editha quino (Quino checkerspot butterfly)1.
10. Mojavean (MOJ): small but complex region borders
VAN and CAL on west, GBA on north, and SON on
south and east. Includes Death Valley, adjacent desert
ranges, and large desert region of southeastern Cali-
fornia, to base of Transverse ranges, corresponding to
DMoj region of The Jepson Manual (Hickman, 1993).
Extends to east through southern Nevada and north-
western Arizona to extreme southwestern Utah
(MacMahon, 2000). Predominately shrubby desert
dominated by endemic Joshua-tree Yucca brevifolia
(Agavaceae), with saltbush (Atriplex) scrub character-
istic of alkaline basins. Other characteristic species
Volume 91, Number 1
2004
183Katinas et al.
Geographical Diversification
include Agavaceae: Yucca schidigera; Asteraceae:
Ambrosia dumosa; Cactaceae: Echinocactus polyce-
phalus, Ferocactus achantoides; and Zygophyllaceae:
Larrea divaricata subsp. tridentata. Some endemic
plants include Agavaceae: Yucca brevifolia; Astera-
ceae: Amphipappus fremontii; Caryophyllaceae: Sco-
pulophila rixfordii; Cactaceae: Opuntia chlorotica;
Plantaginaceae: Penstemon calcareus; Polygonaceae:
Gilmania luteola. Endemic fauna include Reptiles:
[Phrynosomatidae] Uma scoparia (Mojave fringe-toed
lizard)1,7; Mammals: [Muridae] Microtus californicus
scirpensis (Amargosa vole)1; [Sciuridae] Spermophilus
mohavensis (Mojave ground squirrel)1,2; Insects: [Or-
thoptera, Stenopelmatidae] Ammopelmatus kelsoensis
(Kelso Dunes jerusalem cricket)1,8.
11. Sonoran (SON): ranges from the southern border of
the MOJ in southeastern California, south throughout
Baja California, Mexico, east through most of south-
western Arizona, and southeast through Sonora, Mex-
ico. Very characteristic plants of the region include
columnar cacti such as Carnegiea gigantea (saguaro)
and Pachycereus pringlei (Cactaceae), trees such as
Yucca valida (Agavaceae), Cercidium floridum, and C.
microphyllum (Cercidiphyllaceae), and shrubs such as
Acacia greggii (Fabaceae), Krameria grayi (Krameri-
aceae), and Larrea divaricata subsp. tridentata (Zyg-
ophyllaceae). Endemic plant taxa include Onagraceae
(tribe Lopezieae): Lopezia clavata, and species in var-
ious other families, including Agavaceae: Agave au-
rea; Cactaceae: Opuntia rosarica; Fabaceae: Acacia
brandegeana, A. goldmanii, Errazurizia benthami;
Fouquieriaceae: Fouquieria columnaris; Lamiaceae:
Hyptis laniflora; Sapindaceae: Aesculus parryi; Sapo-
taceae: Sideroxylon peninsulare. Endemic fauna in-
clude Birds: [Emberizidae] Aimophila carpalis (ru-
fous-winged sparrow)1,3; [Hydrobatidae] Oceanodroma
macarodactyla (Guadalupe storm petrol, possibly ex-
tinct)1,3; Insects: [Coleoptera, Carabidae] Calathus
peropacus (ground beetle; Liebherr, 1991b), Pelma-
tellus parallelus (ground beetle)1,8; [Hymenoptera, An-
thophoridae] Agapanthinus (digger bees; Ayala et al.,
1993).
12. Chihuahuan (CHI): borders SON and SMO on west,
GBA and ROC on north, NAP and TAM on east, and
MAS on south. Extends from eastern Arizona and
central New Mexico through trans-Pecos Texas and
south into Mexico, including most of Chihuahua and
Coahuila, eastern Durango, and northern Zacatecas.
Cooler desert than the Sonoran Desert, dominated by
shrubby Larrea divaricata subsp. tridentata and spe-
cies of Acacia, Agave, Dalea, Ephedra, Flourensia,
Fouqueria, and Jatropha, among others. Trees, mainly
species of Yucca and Opuntia, are found only along
larger streambeds. Endemic plant species include As-
teraceae: Ambrosia johnstoniorum, Flaveria anomala,
Gaillardia gypsophila; Chenopodiaceae: Meiomeria
stellata; Fabaceae: Dalea filiciformis; Hydrophylla-
ceae: Phacelia gypsogenia. Endemic fauna include
Fishes: [Cyprinidae] Campostoma ornatum (Mexican
stoneroller)1,6, Notropis chihuahua (Chihuahua shin-
er)1,6; Reptiles: [Teiidae] Cnemidophorus tigris vari-
olosus)1,7; Insects [Coleoptera, Carabidae] Agonum ex-
timum (ground beetle; Liebherr, 1991a).
13. Tamaulipan (TAM): ranges from southeastern Texas
to western Coahuila and most of Nuevo Leo?n and Ta-
maulipas in Mexico, excluding southern parts of these
states. Bounded on west by CHI and SMR and on
north in southern Texas by complex interface with
NAP, APP, and ATL. In Texas, corresponds to ??South
Texas Plains?? area of Correll and Johnston (1970).
Characterized mostly by thornscrubs or mesquite-
grasslands, moister than CHI desert to the west. Veg-
etation is largely open shrub- and grasslands with
Acacia, Aloysia, Celtis, Condalia, Prosopis, Ziziphus,
and other spiny species. Endemic plant species in-
clude Boraginaceae: Heliotropium torreyi; Ebenaceae:
Diospyros palmeri; Euphorbiaceae: Croton torreyanus;
Fabaceae: Acacia rigidula, Mimosa malacophylla;
Lauraceae: Phoebe tampicensis; Lentibulariaceae:
Pinguicula gracilis; Plantaginaceae: Leucophyllum
frutescens; Polygalaceae: Polygala glandulosa; Rham-
naceae: Condalia hookeri; Rutaceae: Amyris cordata.
Endemic fauna include Fishes: [Cichlidae] Cichlaso-
ma cyanoguttatum (Rio Grande cichlid)1,6; Mammals:
[Sciuridae] Cynomys mexicanus (Mexican prairie dog;
Fa & Morales, 1993)2; [Talpidae] Scalopus montanus
(Coahuila mole)1; Insects: [Coleoptera, Carabidae]
Platynus bacatellus (ground beetle; Liebherr, 1992).
14. Sierra Madre Occidental (SMO): borders SON and a
coastal strip of the Central American Neotropical area
(NE) on west, and CHI, the Altiplano of central Mex-
ico (MAS), and the Trans-Mexico Volcanic (TMV) re-
gions on the east and south. Starts near U.S.?Mexico
border and extends southeast through western Chi-
huahua, Durango, a small part of Zacatecas, eastern
Sinaloa and Nayarit, to central Jalisco. The main cor-
dillera consists of an extensive volcanic terrain from
200 to 2200 m, with a pronounced eastern tilt. The
region is characterized by a variety of habitats in-
cluding both dry and subtropical forests at lower el-
evations, dry mixed forests at mid-elevations, and
pine/oak forests above 2000 m. Endemic plants in-
clude Onagraceae (tribe Lopezieae): Lopezia ciliatula,
L. conjugens, L. gentry, L. laciniata, L. lopezioides, L.
ovata, L. semeiandra, L. sinaloensis, and L. suffrutes-
cens, and species in various other families, including
Asteraceae: Alvordia congesta, Hofmeisteria sinaloen-
sis, Perityle grandifolia; Cactaceae: Ferocactus
schwarzii, Mamillaria rubidea, Stenocereus martinezii;
Crassulaceae: Echeveria kimnachii, Sedum copalense;
Ericaceae: Arbutus madrensis; Euphorbiaceae: Ditaxis
sinaloae; Polygonaceae: Ruprechtia occidentalis. En-
demic fauna include Birds: [Picidae] Campephilus im-
perialis (imperial woodpecker)1,3; Insects: [Coleoptera,
Carabidae] Elliptoleus olisthopoides (ground beetle;
Liebherr, 1991a); [Neuroptera, Myrmeleontidae] Mar-
acandula apicalis (antlion)8.
15. Trans-Mexican Volcanic Belt (TMV): extends in nar-
row, slightly northwest to southeast band in central
Mexico, from central Jalisco and Guerrero through
southern Estado Mexico barely to Puebla. Borders
SMO and the coastal NE strip on west and south,
MAS on north, and a transitional montane area be-
tween SMR and SMS on east. Major volcanic peaks
(3900?4000 m) covered by Pinus hartwegii and
coarse bunchgrasses Festuca tolucensis, Calamagros-
tis tolucensis, and Muhlenbergia quadridentata. Other
characteristic taxa included species of Achillea, Al-
chemilla, Arenaria, Cerastium, Geranium, Ranuncu-
lus, and Trifolium. Among the very large number of
endemic plant species are Onagraceae (tribe Lope-
zieae): Lopezia longiflora; at least seven endemic al-
pine species of Asteraceae: Cirsium nivale, Gnaphal-
ium sarmentosum, G. vulcanicum, Senecio calcarius,
184 Annals of the
Missouri Botanical Garden
S. gerberaefolius, S. procumbens, and S. roseus; and
many other taxa, including Garryaceae: Garrya lon-
gifolia; Meliaceae: Cedrela saxatilis; Orchidaceae:
Pleurothallis nigriflora; Oxalidaceae: Oxalis stoloni-
fera, O. cuernavacana. Endemic fauna include Am-
phibians: [Ambystomidae] Ambystoma (Rhyacosire-
don) rivularis (Michoaca?n stream salamander)4;
Mammals: [Muridae] Neotomodon altstoni (Mexican
volcano mouse)2, Reithrodontomys chrysopsis (volcano
harvest mouse)2; Insects: [Coleoptera, Carabidae] Cal-
athus azteca, Elliptoleus corvus, E. luteipes (ground
beetles; Liebherr, 1991b), Platynus machetellus
(ground beetle; Liebherr, 1992); [Hymenoptera, An-
thophoridae] Loxoptilus (digger bees; Ayala et al.,
1993).
16. Mexican Altiplano (MAS): in central Mexico lies be-
tween CHI on north, the mountains of SMO on the
west and SMR on the east, and TMV on the south.
Includes central and southern Zacatecas, southeast-
ern Durango, eastern Jalisco and Michoaca?n, northern
Estado Me?xico, western San Luis Potos?? and Hidalgo,
the Federal District, Aguascalientes, Guanajuato, and
Quere?taro. This region is characterized by mixed, less
xeromorphic tree communities of Acacia, Ipomoea,
and Opuntia. Endemic plant species include Agava-
ceae: Yucca queretaroensis; Asteraceae: Acourtia eli-
zabethiae; Berberidaceae: Berberis albicans; Cacta-
ceae: Lophophora diffusa, Mammillaria camptotricha;
Fabaceae: Acacia sororia; Lentibulariaceae: Pinguic-
ula agnata. Endemic fauna include Insects: [Cole-
optera, Carabidae] Agonum suturale (ground beetles;
Liebherr, 1991a); [Hymenoptera, Halictidae] Para-
gapostemon (halictic bees; Ayala et al., 1993).
17. Sierra Madre Oriental (SMR): borders CHI and MAS
on west and TAM on east, including parts of southern
Coahuila and Nuevo Leo?n, eastern Zacatecas, San
Luis Potos?? and Hidalgo, most of Tlaxcala, western
Puebla, and a small part of western Veracruz and
southwestern Tamaulipas. A geologically complex
montane area with high levels of endemism in the
relatively moist eastern part; lower elevations in the
southeast support tropical evergreen forest. At middle
to higher elevations (1000?2000 m), strips of warm-
temperate to subtropical mesophytic forest occur, with
deciduous/semi-evergreen species. Pine and/or oak
forest occur at highest elevations. The mixed forest
contains genera characteristic of the Appalachian re-
gion, such as Carpinus, Cornus, Fagus, Hamamelis,
Liquidambar, Pinus, Platanus, and Quercus, as well
as more typically tropical elements, like Eugenia, Me-
liosma, Rapanea, and Turpinia. Among the very large
number of endemic plants are Onagraceae (tribe Lo-
pezieae): Lopezia nuevoleonis; and many other taxa,
including Caprifoliaceae: Viburnum cuneifolium; Ce-
lastraceae: Wimmeria concolor; Clethraceae: Clethra
pringlei; Crossosomataceae: Velascoa; Fagaceae: Fa-
gus mexicana, Quercus germana, Q. rysophylla; Jug-
landaceae: Juglans mollis; Oleaceae: Forestiera race-
mosa; Sabiaceae: Meliosma alba. Endemic fauna
include Reptiles: [Anguidae] Abronia graminea (ter-
restrial arboreal alligator lizard)7, A. taeniata (bro-
meliad arboreal alligator lizard)7; Insects [Coleoptera,
Carabidae] Calathus rotgeri, C. potosi (ground beetles;
Liebherr, 1991b), Platynus robustulus (ground beetle;
Liebherr, 1992); [Lepidoptera, Papilionidae; Llorente-
Bousquets & Luis-Mart??nez, 1993] Parides alexiares
(Oaxacan swallowtail), Priamides erostratinus (swal-
lowtail), Protesilaus epidaus tepicus (swallowtail).
18. Sierra Madre del Sur (SMS): east-west oriented moun-
tain area, ranging from 1200 to 3500 m, including
eastern Guerrero, northwestern Oaxaca, and southern
Puebla and Morelos. Connects to north with TMV,
MAS, and SMR, but mostly surrounded by lowland
NE, and as such is southernmost part of the Madrean
Region (Takhtajan, 1986). Includes mesic habitats
with temperate evergreen forests and woodlands. The
diversity of these woodlands is very high, including
species of Quercus and Juniperus, as well as genera
of more southern, tropical derivation. Endemic plants
include Onagraceae: (tribe Fuchsieae) Fuchsia ravenii
and (tribe Lopezieae): Lopezia smithii, as well as Aga-
vaceae: Yucca mixtecana; Lauraceae: Mocinnodaphne
cinnamomoidea; Malvaceae: Hibiscus tenorii; Melas-
tomataceae: Miconia teotepecensis; Ruscaceae:
Maianthemum amoenum, M. macrophyllum, M. com-
altepecense. Endemic fauna include Amphibians:
[Plethodontidae] Thorius grandis (grand minute sala-
mander), T. infernalis (Atoyac minute salamander);
Reptiles: [Anguidae] Abronia deppii (alligator lizard);
Insects: [Coleoptera, Carabidae] Calathus ovipennis,
Elliptoleus crepericornis, E. whiteheadi (ground bee-
tles; Liebherr, 1991b), Platynus platynellus (ground
beetle; Liebherr, 1992).
19. Neotropical (NE): large region, essentially the Neo-
tropical Kingdom of Takhtajan (1986), comprises ev-
erything south of the Madrean and North American
regions. For purposes of this analysis, NE includes a
broad spectrum of tropical sub-regions, from the
southernmost, tropical part of the Florida Peninsula
through the islands of the Caribbean region, most of
the coastal plains of Mexico, and all of Central Amer-
ica to most of South America. Among the very large
number of endemic plant taxa are Onagraceae, tribe
Hauyeae and numerous species of Fuchsia (tribe
Fuchsieae) and Ludwigia (tribe Jussieeae), and the
plant families Brunelliaceae, Cyclanthaceae, Desfon-
tainiaceae, and Marcgraviaceae. Endemic fauna in-
clude Amphibians: [Hylidae] Gastrotheca (Notodel-
phis) ovifera (giant marsupial frog)4; Reptiles: [Boidae]
subfamily Boinae (boas and constrictors)7; Birds: fam-
ily Rheidae (rheas)3; Mammals2,5: [Camelidae] Lama
(alpacas, guanacos, llamas); family Caviidae (cavies,
guinea pigs); family Chinchillidae (chinchillas and
viscachas); [marsupials, Microbiotheriidae] Dromi-
ciops (monitos del monte).
20. East Palearctic (EP): defined here to include the
northeast Asian parts of the Circumboreal Region and
essentially all of the diverse Eastern Asiatic Region
of Takhtajan (1986), including the eastern Himalayas,
most of China, the Korean Peninsula, Japan and the
north Pacific Ocean island series. The flora of this
region is enormous and very rich in endemics, in-
cluding in Onagraceae several species of Circaea
(tribe Circaeeae; Boufford, 1982) and Epilobium (tribe
Epilobieae; Chen et al., 1992), as well as the endemic
families Cephalotaxaceae, Ginkgoaceae, and Trochod-
endraceae, and more than 300 endemic genera [e.g.,
Apiaceae: Tetrapanax; Berberidaceae: Nandina; Cor-
naceae: Aucuba; Lardizabalaceae: Akebia; Rosaceae:
Chaenomeles; Rutaceae: Poncirus; Taxodiaceae: Cryp-
tomeria]. Endemic fauna include Fishes: [Siluridae]
Silurus asotus (Amur catfish)6; Reptiles?Crocodilians:
family Gavialidae (gharial)7; Birds [Phasianidae] Gal-
Volume 91, Number 1
2004
185Katinas et al.
Geographical Diversification
lus gallus (red jungle fowl, chicken)3; Mammals2,5: or-
der Dermoptera (flying lemurs); family Hylobatidae
(gibbons and lesser apes); [Leporidae] Pentalagus
(Ryukyu rabbit).
21. West Palearctic (WP): defined here to include Euro-
pean and west Asian parts of the Circumboreal Re-
gion (Takhtajan, 1986), essentially everything west of
EP in Eurasia. The flora includes many endemic
plants, including Apiaceae: Agasyllis, Endressia, Tho-
rella; Asteraceae: Berardia; Boraginaceae: Megacar-
yon, Trigonocaryum; Brassicaceae: Microstigma,
Pseudovesicaria; Fabaceae: Petteria; Gesneriaceae:
Haberlea). Endemic fauna include Fishes: [Siluridae]
Silurus aristotelis (Aristotle?s catfish)6; Amphibians:
[Pelobatidae] Pelobates (European spadefoot toads)4;
Mammals: [Bovidae] Ovis musimon (mouflon sheep)2,5.