NOVON 14: 124?133. 2004.
Resolving a Nomenclatural and Taxonomic Problem in Mexican
Oenothera sect. Hartmannia (Tribe Onagreae, Onagraceae)
Warren L. Wagner
United States National Herbarium, Department of Systematic Biology, Botany, MRC-166,
P.O. Box 37012, Smithsonian Institution, Washington, DC 20013-7012, U.S.A.
wagner.warren@nmnh.si.edu
ABSTRACT. Study of type material from the trans-
volcanic region of Mexico of two species of Oen-
othera sect. Hartmannia (tribe Onagreae, Onagra-
ceae), currently known as Oenothera deserticola
(Loesener) Munz and O. purpusii Munz, indicates
that they represent the same species. Thus, the lat-
er name O. purpusii becomes a new synonym of O.
deserticola. Also, a neotype is designated herein for
O. deserticola. The only available name for the sec-
ond species, previously incorrectly called O. deser-
ticola, is Hartmannia montana Rose, but since O.
montana is already occupied, a new name, O. ori-
zabae, is here proposed. A previously unreported
chromosome count of n 5 7 is given for O. deser-
ticola. While examining collections to resolve this
problem, a series of specimens from the Sierra Ma-
dre Occidental was determined to represent a third
species here described as O. luciae-julianiae.
These three species can be distinguished by a suite
of characters involving habit, petal color, and cap-
sules. Oenothera deserticola is characterized by de-
cumbent stems, morning-opening flowers, rose pur-
ple petals, and angled, but unwinged capsules with
an attenuate apex, while O. luciae-julianiae has
erect or ascending stems, evening-opening flowers,
white petals, and narrowly winged capsules with an
abruptly acuminate apex. Oenothera orizabae has
decumbent stems, evening-opening flowers, white
petals, and large-winged capsules with a rounded
apex.
RESUMEN. El estudio de los tipos de Oenothera
deserticola y O. purpusii de la seccio?n Oenothera
seccio?n Hartmannia procedentes de la regio?n tras-
volca?nica de Me?xico, indica que ambos representan
la misma especie. Como resultado, O. purpusii es
considerado sino?nimo de O. deserticola. Una segun-
da especie, originalmente descrita como Hartman-
nia montana, pero cuyo ep??teto espec??fico esta? ocu-
pado en Oenothera, es substituido por el nombre
O. orizabae, el cual es aqu?? propuesto. El estudio
de las colecciones procedentes de la Sierra Madre
Occidental determino? que existe una tercera es-
pecie, la cual es aqu?? descrita como O. luciae-ju-
lianiae. Estas tres especies pueden ser distinguidas
por una serie de caracteres relacionados al ha?bito,
color de pe?talo y de las ca?psulas. Oenothera deser-
ticola es caracterizada por tallos decumbentes, flo-
res de apertura matutina, pe?talos purpu?reo-rosados
y ca?psulas angulosas, a?pteras y atenuadas hacia el
a?pice, mientras que la especie de la Sierra Madre,
aqu?? descrita como O. luciae-julianiae, tiene tallos
erectos o ascendentes, flores que abren al anoche-
cer, pe?talos blancos y ca?psulas estrechamente ala-
das con un a?pice abruptamente acuminado. Oenot-
hera orizabae tiene tallos decumbentes, flores que
abren al anochecer, pe?talos blancos y ca?psulas ala-
das, grandes, con el a?pice redondeado.
Key words: evening-primrose, Mexico, Oeno-
thera sect. Hartmannia, Onagraceae.
Nearly one third of the 120 species of the genus
Oenothera L. occur in Mexico. Recent focus on the
phylogeny of the family Onagraceae, especially of
the most diverse tribe Onagreae (Levin et al.,
2003), along with analyses of biogeographic pat-
terns of tribes Epilobieae, Gongylocarpeae, and
Onagreae (Katinas et al., in press) have resulted in
the need to resolve a nomenclatural problem and
describe a new species.
Two relatively uncommon species from the trans-
volcanic region of Mexico, Oenothera deserticola
(Loesener) Munz and O. purpusii Munz, have had
a confused application of names since the latter was
described in a revision of Oenothera sect. Hart-
mannia (Munz, 1932). A brief history leading up
to the confusion clarifies the problem. The first spe-
cies was described as Hartmannia montana J. N.
Rose (1905). The second was published as Xylo-
pleurum deserticolum Loesener (1913). Both of
these species were included in Munz?s revision of
Oenothera sect. Hartmannia (Munz, 1932), but for
some reason he was confused on the correct appli-
cation of Xylopleurum deserticolum. Munz?s descrip-
tion of O. deserticola clearly fits the taxon that J.
N. Rose described as Hartmannia montana (1905).
Volume 14, Number 1
2004
125Wagner
Oenothera Sect. Hartmannia
It was characterized by decumbent stems, white
petals, and large-winged capsules with a rounded
apex. Munz cited a number of collections of it, in-
cluding the type of Hartmannia montana, and
placed Rose?s name in synonymy of O. deserticola.
Munz also cited all four syntype collections given
in the original publication of Xylopleurum deserti-
colum (Loesener, 1913). It is not clear if Munz had
actually seen any of the syntype collections or if he
merely cited them from Loesener?s protologue,
while at the same time selecting one of them as the
type. For reasons unknown to me, Munz was con-
fused because at least one of the syntypes, Seler
5614 (photo US), and likely all four judging from
Loesener?s description, is clearly the same taxon as
the one he described in the same paper (1932) as
the new species O. purpusii Munz. This species was
characterized by decumbent stems, rose-purple
petals, and smaller, angled, but unwinged capsules
with an attenuate apex.
A photo of one of the four syntypes was taken
before all four were destroyed in the Berlin her-
barium during World War II. This photo is repro-
duced here in Figure 1. I had hoped to confirm the
characteristics of original material of O. deserticola
by either locating duplicates of the lectotype, other
syntype collections, or photographs of any of the
other three syntypes, but none were found by the
collections managers who kindly searched for them
at the herbaria known to have received Seler col-
lections (A, B, CAS, F, GH, K, MEXU, NY, US).
Despite not having any of Loesener?s original ma-
terial, it is clear from the leaves and dehisced cap-
sule shown in the photograph that O. deserticola
represents the same taxon that has gone under the
name O. purpusii since 1932. The name Oenothera
deserticola has priority over O. purpusii, and there-
fore is the correct name. This conclusion is further
supported by Loesener?s original description
(1913), as characterized earlier.
The other species in question was first described
in 1905 as Hartmannia montana Rose. Since the
specific epithet montana is already occupied in Oe-
nothera, a new name, O. orizabae, is proposed here.
During the course of study of these two species
using material from a number of primarily Ameri-
can and Mexican herbaria, it became clear that a
significant number of Mexican collections from the
Sierra Madre Occidental, from Chihuahua south
through Durango to Jalisco and Guanajuato that
were identified as O. deserticola by P. H. Raven,
myself, or others over the past three decades rep-
resents an undescribed species characterized by
erect or ascending stems, white petals, and narrow-
ly winged capsules with an abruptly acuminate
apex. It is here described as O. luciae-julianiae. It
has a distribution allopatric from both O. orizabae
and O. deserticola. The following key distinguishes
them from one another.
KEY TO SPECIES OF MEXICAN OENOTHERA SECT. HARTMAN-
NIA
1a. Capsules winged, acuminate to rounded at apex;
petals white at anthesis, fading purple.
2a. Stems decumbent, ascending toward the
apex; cauline leaf blades 1?3 cm wide, nar-
rowly ovate, occasionally elliptic, subentire to
subdenticulate; capsule body 15?26 mm
long, obovoid, apex rounded, the margins
winged, the wings 2.3?4 mm wide, the sterile
stipe stout, 15?50 mm long; capsule body ap-
parently dehiscing only at apex . . . O. orizabae
2b. Stems erect to ascending; cauline leaf
blades 0.5?1.1(?3) cm wide, elliptic to lan-
ceolate or narrowly elliptic-ovate, denticu-
late to serrulate; capsule body 8?18(?25)
mm long, clavate or narrowly obovoid, apex
obtuse to bluntly acuminate, the wings 1.3?
2 mm wide; the sterile stipe slender, 7?35
mm long; capsule body dehiscing from about
half its length to nearly throughout . . .
. . . . . . . . . . . . . . . . . . . O. luciae-julianiae
1b. Capsules angled, but not winged, attenuate at
apex; petals rose-purple at anthesis, fading dark-
er . . . . . . . . . . . . . . . . . . . . . . . O. deserticola
Oenothera deserticola (Loesener) Munz, Amer.
J. Bot. 19: 758. 1932. Xylopleurum desertico-
lum Loesener, Repert. Sp. Nov. 12: 238. 1913.
TYPE: Mexico. Distrito Federal: Contreras,
Lyonnet 532 (neotype, designated here,
MEXU-238843; isoneotypes, GH, K not seen,
MEXU [3], MO, NY, US). Figure 2.
Oenothera purpusii Munz, Amer. J. Bot. 19: 759. 1932.
Syn. nov. TYPE: Mexico. Ixtaccihuatl, open woods,
1903, C. A. Purpus 1839 (holotype, POM 32827 not
seen; isotypes, F, G not seen, GH, MO, NY, UC, US).
Perennial herb with usually several or sometimes
more, decumbent or sometimes ascending when
short, branched or occasionally simple stems 5?
20(?36) cm long, usually reddish purple or occa-
sionally pale purple, strigillose, rarely with a few
longer erect hairs, often producing new rosettes via
rhizomes up to 6?7 cm long, from a thick somewhat
woody caudex; root fleshy and thickened in age.
Rosette leaf blades 4?6 3 1?1.7 cm, oblanceolate
to elliptic, sparsely to moderately strigillose, ap-
parently quickly deciduous; petiole 0.4?1.6 cm;
cauline leaf blades 1?6.5 3 0.5?1.8 cm, elliptic to
elliptic-oblanceolate or narrowly so, subserrate to
weakly sinuate-toothed, apex obtuse to acute,
sparsely to moderately strigillose; petiole 0.1?1.1
cm long. Flowers opening near sunrise (Iltis et al.
126 Novon
Figure 1. Reproduced photograph of Seler 5614, a Berlin (B) syntype of Xylopleurum deserticolum Loesener no longer
extant, taken as part of the Field Museum?s (F) Types of the Berlin Herbarium project. Copies of the photograph are
in MICH, MO, NY, POM, and US. The photograph was scanned into Photoshop 6.5, and then a dehisced capsule
showing the long apex of the valves allowing for unambiguous identification was cut, enlarged, and pasted into the
upper left-hand corner (obscuring two small branches evident in the original). A white box on the full photograph
indicates the part cut and enlarged. The leaves and part of a stem were removed from the inset for clarity.
202 says evening); floral tube, sepals, and ovary
densely strigillose, and ovary usually also densely
hirtellous with hairs up to 2 mm long; floral tube
4.5?11 mm long; sepals 7.5?16 mm long; free tips
in bud absent or rarely present and ca. 0.1?0.2 mm
long; petals 8.5?17 mm long, rose-purple fading
darker after pollination; filaments 5.5?8 mm long,
rose-purple; anthers 2.5?4.5 mm long, cream; pol-
Volume 14, Number 1
2004
127Wagner
Oenothera Sect. Hartmannia
Figure 2. Oenothera deserticola (Loesener) Munz. ?A. Habit, showing decumbent stems from a branched rhizomatous
base (Arroyo 182, MO, and Balogh 1005, US). ?B. Bud, floral tube, and ovary, showing the lack of free sepal tips
and pubescence pattern (Arroyo 182, MO). ?C. Flower, showing petal shape and overlap of petals (Hinton 9104, US).
?D. Young capsule showing shape, attenuate apex, and sterile stipe (Lyonnet 532, MEXU). ?E. Dehisced capsule
showing length of dehiscence and seeds clustered on placentas (Straw & Gregory 1116, GH). ?F. Dehisced capsule
showing shape of open valves (Lyonnet 532, US).
len cream, . 90% fertile; style 12?21 mm long;
stigma surrounded by the shedding anthers at an-
thesis or slightly elevated above it; stigma lobes
2.5?4 mm long. Capsule body 10?22 mm long,
rose-purple to green with purple tinge, the body
narrowly ellipsoid to clavate, apex attenuate, angled
or rarely with a narrow wing up to 0.5 mm wide;
sterile stipe slender, 7?17 mm long; capsule body
128 Novon
dehiscing nearly throughout; seeds clustered in
each locule, 1?1.2 mm long, 0.4?0.6 mm thick,
brown. Gametic chromosome number, n 5 7 (Ra-
ven, unpublished).
Distribution. Oenothera deserticola occurs in
open forests of Pinus, Pinus-Quercus, or occasion-
ally Abies, Alnus, and Salix, on sandy open sites or
steep banks, in the mountains of the Trans-Mexican
Volcanic region from the northeastern Michoaca?n
and central Hidalgo south to Me?xico and Orizaba,
Veracruz, from (2100)2500 to 3400 m.
The lectotype selected by Munz (1932), but now
destroyed, was collected in Mexico, D.F., El De-
sierto de los Leones, May 1909, W. Ho?pfer s.n. (C.
& E. Seler 5280) (B destroyed). The lectotype and
three additional syntypes (without further locality
Uhde 1222; El Desierto de los Leones, W. Ho?pfer
s.n. (labeled as Seler 5614) [photos: MICH, MO,
NY, POM, US]; and San Rafael, Tlalmancalo, Seler
5319) were destroyed during World War II (Chris-
toph Oberprieler, pers. comm. 2001).
Oenothera deserticola is a member of section
Hartmannia, which can be subdivided into three
groups of species based on petal color and time of
flowering. With its rose-purple petals and morning
flowering, O. deserticola appears to be in a group
with other morning-flowering species with purple
petals, including O. platanorum P. H. Raven & D.
R. Parnell, O. rosea L?He?ritier de Brutelle ex Aiton,
and O. texensis P. H. Raven & D. R. Parnell. These
species share angled, but not winged capsules and
no free sepal tips in bud or tips free and minute
(0.1?0.2 mm long).
The geographic and elevational range of Oenot-
hera deserticola broadly overlaps the range of O.
orizabae. One collection (Barkley et al. 2438) is a
mixed collection of O. deserticola and O. orizabae
suggesting that they occur sympatrically at some
localities; however, there is no documentation of
hybridization. Hybridization must be strongly lim-
ited by the different timing of flowering, with flow-
ers of O. deserticola open during the day and those
of O. orizabae open at night.
Specimens examined (those marked by * are chromosome
determination vouchers). MEXICO. Distrito Federal:
Desierto de los Leones, *Raven 15424 (also flavonoid
voucher) (TEX); hwy. 190, betw. Puebla & Mexico City,
Ahshapanek 701 (TEX); Contreras Canyon, SW of Mexico
City, Munz 15000 (GH, MO); Chapultepec III, Valle del
Silencio, Wonderly 217 (MEXU, NMC); Cerro de Esqui-
huil, delegacio?n de Mipa Alta, Ventura 2804 (MEXU, MO,
NY); R??o Fr??o, Russell & Souviron 82 (US); Volca?n Pelado,
ladera E, Mondrago?n s.n. (MEXU); near Estacio?n La
Cima, Serran??a del Ajusco, Rzedowski 19840 (MICH, MO,
TEX); Tlalpan, Volcan Ajusco, Reyes s.n. (MEXU); lava
fields ca. 2 km SSW of La Cima R.R. Station on either
side of old Hwy. 95 on top of Serjana de Ajusco, Iltis et
al. 202 (MICH, RSA); Cerro Tepetlahualo, delegacio?n de
Milpa Alta, Ventura 1412 (MEXU); Santa Rosa, delega-
cio?n de A. Obregon, Ventura 2720 (MEXU, MO); 1 mi.
SE of Puerto del Aire, Barkley et al. 2438 (MICH, TEX)
[both sheets mixed collection with O. orizabae]. Hidalgo:
Cerro de los Pitos, Matuda 21562 (MEXU [2]); El Chico,
Cerro de Las Ventanas, Gentry et al. 32180 (MO); Parque
Nacional El Chico, Ortiz 10 (MEXU); Metzquititlan, Car-
pinteros, 20 km E Metzquititlan, Hernandez 6806 (MO);
Sierra de Pachuca, Rose & Hay 5611 (US). Me?xico: on
hwy. Me?xico to Puebla, Munz 15064 (POM); Monte de R??o
Fr??o, km 49, road from Mexico City to Pueblo, Mexia
2696a (UC); near Salazar, Rose & Painter 7027 (US); Ne-
vada de Toluca, Rose & Painter 7873 (US); El Crucerco,
Temascaltepec, Hinton 521 (POM); Cerro de Leo?n, Valle
de Mexico, Matuda 19128 (MEXU [2]); Paraje Provincial,
Balls 4173 (UC, US); San Rafael, ladera W del Iztacci-
hua?tl, Sa?nchez 8 (MEXU); Ixtapaluca, Estacio?n Experi-
mental de Ensen?anza y Investigacio?n de Zoquiapan, Koch
& Magan?a 75242 (MEXU, MO, NY); Llano Grande Gap,
near R??o Fr??o, Sharp 4496 (MEXU, RSA); Nat. Park La-
gunas de Zempoala, Cole 49 (MEXU), McAdams 57
(MICH), Traylor 55 (MEXU); Comunidad, Temascaltepec,
Hinton 860 (GH, NY, POM); Cumbre, Temascaltepec,
Hinton et al. 7478 (GH, LL, MICH [2], MO, NY, POM,
TEX, UC, US); Cumbre Trojes, Temascaltepec, Hinton et
al. 8272 (MEXU, MICH, NY, UC, US); Mt. Popocatapetl,
Nelson 10 (US); 10 km al NE del Entronque a Sultepec,
Flores & Terpa?n 829 (MEXU); Vallee de Bravo, 0.8 mi. S
of Cajones, 9500 ft., Balogh 1005 (US); 55 km SE of
Mexico City, 10,500 ft., Weaver 712 (POM, US); near To-
luca, Schery 64 (MO); Ocuilan, Matuda 32454 (MEXU).
Michoaca?n: near base of Cerro de Tecolote near Zacapu,
Sharp 45531 (RSA); Cerro del Burro, Santa Clara del Co-
bre, Pe?rez 53 (MEXU, MO), Escobedo 1400 (MO); Cerro
Prieto, Nuevo Parangaricutiro, Medina 2684 (MEXU); En
El Salto, a 7 km al E de Ocampo, Melchor Ocampo, Mar-
t??nez & Torres 419 (MEXU); Ocampo, 11 km al SE de
Ocampo, en el Cerro El Chivati, Soto Nu?n?ez & Solo?rzano
12609 (MEXU); Quere?ndaro, cerca de San Jose? de la
Cumbre, Santos 1301 (MEXU); ladera SW del Cerro San
Andre?s, Zinape?cuaro, Zamudio 5520 (MEXU, MO); lado
N de La Presa La Gachupina, Jasso 1029 (MEXU); ca. 18
mi. S of Pa?tzcuaro, King & Soderstrom 5189 (TEX, US);
near Paricutin volcano, Eggler 34 (US). Morelos: km 48,
carretera federal, Va?zquez 1871 (MEXU [2]); Lagunas de
Zempoala, *Straw & Gregory 1068 (GH, MEXU, MICH,
RSA, UC); Huitzilac, ladera NE del Lago Hueyapan, Par-
que Nacional Lagunas de Zempoala, Avonce s.n. (MEXU).
Puebla: 4 km E of R??o Fr??o, Roe et al. 343 (MICH, US);
side of Popocatepetl, Miranda & Barkley 17M200 (F,
TEX); El Salto, R??o Fr??o, Boege 3073 (MEXU). Veracruz:
Lomogrande, Mt. Orizaba, Balls 4377 (UC, US). Without
locality: Gregg 697 (MO).
Oenothera orizabae W. L. Wagner, nom. nov.
Hartmannia montana Rose, Contr. U.S. Natl.
Herb. 8: 329. 1905, non Oenothera montana
Nuttall, in Torrey & Gray, Fl. N. Amer. 1: 500.
1840. TYPE: Mexico. El Cima, on the railroad
between Me?xico, D.F., and Cuernavaca, Me?x-
ico, 19 Sep. 1903, J. N. Rose & J. H. Painter
7170 (holotype, US-00450745; isotypes, GH,
MEXU, NY, US). Figure 3.
Volume 14, Number 1
2004
129Wagner
Oenothera Sect. Hartmannia
Figure 3. Oenothera orizabae W. L. Wagner. ?A. Habit, showing decumbent stems from a multi-stemmed base (Straw
& Gregory 1120, GH). ?B. Bud, floral tube, and ovary, showing the free sepal tips and pubescence pattern (Straw &
Gregory 1120, GH). ?C. Flower, showing petal shape and expected non-overlap of petals (Straw & Gregory 1120,
MICH). ?D. Young capsule, showing shape, wings, rounded apex, and sterile stipe (Rose & Painter 7170, holotype,
US). ?E. Dehisced capsule, showing known length of dehiscence (Rose & Painter 7170, isotype, US).
130 Novon
Perennial herb with several decumbent to as-
cending, simple or usually branched stems, 6?46
cm long, the plant hirtellous throughout. Rosette
leaf blades 3?5 3 0.9?1.5 cm, elliptic to oblan-
ceolate, hirtellous; petioles 0.3?1 cm long. Cauline
leaf blades 3?9 3 1?3 cm, narrowly ovate, occa-
sionally elliptic, subentire to subdenticulate; peti-
ole 0.1?2.2 cm long. Flowers opening near sunset;
floral tube, sepals, and ovary densely hirtellous
with hairs up to 1.5 mm long; floral tube 9?15 mm
long; sepals 15?20 mm long; free tips in bud 1.7?
2 mm long; petals 18?22 mm long, white, fading
purple; filaments 15?16 mm long, pale maroon; an-
thers 3?7 mm long, cream; pollen cream-colored,
. 90% fertile; style 20?28 mm long; stigmas held
above the anthers at anthesis, the lobes 4?5 mm
long. Capsule body 15?26 mm long, obovoid, apex
rounded, the margins winged, the wings 2.3?4 mm
wide; the sterile stipe stout, 15?50 mm long; cap-
sule body apparently dehiscing only at apex; seeds
1?1.4 mm long, 0.5?0.7 mm thick, brown. Gametic
chromosome number, n 5 7 (forming 7 pairs at
meiotic metaphase I; Gregory & Klein, 1960; Ra-
ven, unpublished).
Distribution. Oenothera orizabae is scattered in
rocky grasslands in Pinus-Quercus forest at middle
elevations in the Trans-Mexican Volcanos from Mo-
relos and Me?xico to El Chico to the north in Hidalgo,
and Pico Orizaba in Veracruz, at 2980?3000 m.
Oenothera orizabae appears to be allied to a
group of evening-flowering species with white pet-
als currently assigned to section Hartmannia, in-
cluding O. kunthiana (Spach) Munz, and O. tetrap-
tera Cavanilles, but based on recent molecular
studies this white-petaled group may need to be
distinguished as a separate section (Levin et al.,
2004). Another white-flowered species, Oenothera
dissecta A. Gray ex S. Watson, may also belong in
this group, but was most recently assigned to sec-
tion Gauropsis (Wagner, 1984). A single collection
was examined for pollen fertility using Alexander
stain (Alexander, 1969).
Specimens examined (those marked by * are chromosome
determination vouchers and voucher for pollen fertility in-
dicated by 1). MEXICO. Distrito Federal: 1 mi. SE
of Puerto del Aire, Barkley et al. 2438 (MICH, TEX) [both
sheets mixed with O. deserticola]; Estacio?n La Cima, Prin-
gle 10293 (F, GH, MEXU [2], MICH [2], MO, NY, UC,
US), *Raven s.n. (Stanford greenhouse #67-354; flavonoid
voucher) (TEX); Colonia del Valle, Lyonnet 198 (US); ca.
2 km SSW of La Cima R.R. Station, old Hwy. 95, Iltis et
al. 200 (MICH, RSA); Volca?n Pelado, ladera W, Sandoval
230 (MEXU). Hidalgo: El Chico, Lyonnet 2205 (MEXU).
Me?xico: S of Mexico City, Leavenworth & Leavenworth
954 (F); 55 mi. SE of Mexico City, Weaver 713 (POM);
near Gap, near R??o Fr??o, Sharp 4495 (MEXU, RSA); pub-
lic park area W of divide betw. Me?xico & Puebla at the
Estacionamento, Pennell et al. 125 (MO); 1 km al N de
Llano Grande sobre la ladera S del Telapo?n, Espinosa 542
(MO); Llano Grande, Telapo?n, 1Lyonnet 689 (MEXU [2],
US); near R??o Fr??o, Puebla hwy., *Straw & Gregory 1120
(GH, MEXU, MICH [2], RSA); R??o Fr??o, Kenoyer 2485
(GH); just W of R??o Fr??o, 40 mi. E of Mexico City, Man-
ning & Manning 53656a (GH). Morelos: Cuernavaca,
Kenoyer A422 (F); 6 mi. W of Yautepec, Walther 133
(MICH). Veracruz: Pico de Orizaba, Rose & Hay 5672
(US).
Oenothera luciae-julianiae W. L. Wagner, sp.
nov. TYPE: Mexico. Durango: San Dimas,
Mesa del Roble, San Miguel de Cruces,
24.998N, 105.998W, 2740 m, 26 May 1990, A.
Garc??a & S. Acevedo 345 (holotype, US-
3441077; isotypes, ANSM, CHAPA, CIIDIR,
ENCB, IEB, MEXU, UAMIZ (none seen)). Fig-
ure 4.
Ab Oenothera orizabae caulibus erectis ad adscenden-
tes, laminis foliorum caulinorum 0.5?1.1(?3) cm latis
ellipticis ad lanceolatas et denticulatis ad serrulatas, cor-
pore capsulae 8?18(?25) mm longo clavato vel anguste
obovoideo ad apicem obtuso vel acuminato alis ejus 1.3?
2 mm latis stipite sterili tenui 7?35 mm longo.
Perennial herb with few to several, ascending to
erect, simple or occasionally branched stems, the
longer ones becoming decumbent and often devel-
oping lateral branches, 20?50(?90) cm long,
sparsely (very sparsely) to moderately hirtellous,
the hairs 1.5?2.5 mm long, also strigillose through-
out or only in the upper portions of the stem, the
hairs mostly 0.3?0.4 mm long; root a thickened,
often branched taproot. Rosette leaf blades 4?10 3
0.5?2.5 cm, oblanceolate, denticulate to serrulate,
or weakly sinuate-toothed, sparsely to moderately
strigillose, apex obtuse to rounded; petiole 0?1.5
cm long; cauline leaf blades (1.8?)3?7 3 0.5?1.1(?
3) cm, elliptic to lanceolate or narrowly elliptic-
ovate, denticulate to serrulate, apex attenuate,
acute, sparsely to moderately strigillose; petiole 0?
0.5 cm long. Flowers opening near sunset; floral
tube, sepals, and ovary moderately to occasionally
densely strigillose and rarely with scattered hirte-
llous pubescence with hairs up to 1.5 mm long;
floral tube 12?21 mm long; sepals 14?24 mm long;
free tips in bud 1?2 mm long; petals 16?26 mm
long, white fading deep purplish red; filaments 7?
10 mm long, rose-purple or yellow; anthers 4.8?6.5
mm long, cream; pollen cream, ca. 50?60% fertile
(range 26?94%); style 20?30 mm long; stigma el-
evated above to surrounded by the shedding an-
thers at anthesis, the lobes 3.6?6 mm long. Capsule
body 8?18(?25) mm long, gray-green, clavate or
narrowly obovoid, apex obtuse to bluntly acumi-
nate, winged in the upper part or throughout the
Volume 14, Number 1
2004
131Wagner
Oenothera Sect. Hartmannia
Figure 4. Oenothera luciae-julianiae W. L. Wagner. ?A. Habit, showing ascending to erect stems from a several-
stemmed base (Garc??a & Acevedo 345, US). ?B. Bud, floral tube, and ovary, showing the free sepal tips and pubescence
pattern (Reveal & Harley 4095, NY). ?C. Flower, showing petal shape and apparent slight overlap (Garc??a & Acevedo
345, US). ?D. Young capsule, showing shape, wings, obtuse to bluntly acuminate apex, and sterile stipe (Reveal &
Harley 4095, TEX). ?E. Dehisced capsule, showing known length of dehiscence, and valves (although they can be
spreading) (Garc??a & Acevedo 345, US).
132 Novon
body, the wings 1.3?2 mm wide; sterile stipe slen-
der, 7?35 mm long; capsule body dehiscing in up-
per half to nearly throughout; seeds clustered in
each locule, 1.4?1.5 mm long, brown.
Distribution. Oenothera luciae-julianiae is scat-
tered to common in open Pinus or Pinus-Quercus
forests or mixed forests of Abies, Pseudotsuga, Pi-
nus, Quercus, and sometimes with Arbutus, Juni-
perus, or Cupressus, on rocky or open sites, steep
slopes, or moist flats or along streams in the Mex-
ican mountains of the Sierra Madre Occidental from
Chihuahua south through Durango, Guanajuato,
Nayarit, Jalisco, Michoaca?n, and Quere?taro, from
2100 to 2800(?3250) m. Flowering nearly through-
out the year, and documented from February
through November.
Etymology. It is a pleasure to name this attrac-
tive Sierra Madre Occidental species in honor of
my wife, Lucy C. Julian, on the occasion of our 10th
wedding anniversary.
Oenothera luciae-julianiae has gone undetected
for decades of collecting in the Sierra Madre Oc-
cidental. The collections cited herein were deter-
mined most commonly as O. deserticola by P. H.
Raven, myself, or others, but also occasionally as
O. purpusii, O. tetraptera, or O. kunthiana. It was
treated as part of O. deserticola (now correctly
known as O. orizabae) by Raven and D. Parnell
(pers. comm.) in their unpublished revision of sec-
tion Hartmannia. Munz, who revised the section in
1932, never annotated any of the collections, as
very few were made before 1960. J. N. Rose, how-
ever, annotated a single collection from Chihuahua
(Nelson 4848) as a new species, but he never pub-
lished it. Oenothera luciae-julianiae appears to be
allied to a group of evening-flowering species with
white petals currently assigned to section Hartman-
nia, including Oenothera orizabae, O. kunthiana
(Spach) Munz, and O. tetraptera Cavanilles.
Like Oenothera kunthiana of this white-flowered
species group of section Hartmannia, O. luciae-ju-
lianiae appears to be a permanent translocation
heterozygote (PTH) species. In PTH species a ring
of 14 chromosomes is usually formed in meiotic
metaphase. I have not yet been able to obtain cy-
tological material to examine meiosis in this spe-
cies, and thus current data are only suggestive of
this condition in O. luciae-julianiae. PTH species
in the Onagraceae are nearly always autogamous
(Raven, 1979). The stigma is usually surrounded
by the shedding anthers at anthesis in O. luciae-
julianiae, suggesting that it is predominately autog-
amous. Another feature of PTH species is the bal-
anced lethals in pollen and ovules, which can be
observed in lowered pollen fertility and fewer ma-
ture seeds (see Cleland, 1972). I examined pollen
fertility of as many collections as possible of O.
luciae-julianiae. In the 15 collections I examined
with Alexander stain (Alexander, 1969; vouchers
noted with brackets in the exsiccatae) pollen fer-
tility ranged from 26% to 94%, a very wide range,
but suggestive nevertheless that O. luciae-julianiae
is probably a PTH species. Typically, PTH species
have about 50% pollen fertility on average, but all
exhibit a range of fertility. For example, Oenothera
nutans G. F. Atkinson & Bartlett exhibited a similar
wide range of fertility (48% to 84%) in a detailed
study (Wasmund, 1990). Raven (1979) pointed out
that most PTH species are annuals or biennials,
with about 10% of the known PTH species in Ona-
graceae being perennial. If O. luciae-julianiae
proves to be a PTH species, it will represent an-
other atypical species, as it clearly has a perennial
habit from an enlarged root. Oenothera luciae-julia-
niae does not appear to be closely related to other
species of the white-flowered species group of sec-
tion Hartmannia. It may share a common ancestor
with O. tetraptera, an outcrossing pair-forming spe-
cies that appears to be directly related to the other
PTH species in this group, O. kunthiana.
Paratypes (those used to study pollen fertility have %
fertile pollen given in square brackets). MEXICO. Chi-
huahua: ca. 51 mi. S of Creel, Straw & Forman 1900
(RSA) [26%]; Llano Grande, Pennington 181 (TEX)
[37%]; Guachochi, 8 km al W de Cabo?rachi, Herna?ndez
8778 (MEXU); Ocampo, Cascada de Basaseachi, Tenorio
& Torres 4510 (MEXU); Urique, Bye et al. 15612 (MEXU)
[90%], Tenorio et al. 9935 (MEXU) [62%]; base of Mt.
Mohinora, 8 mi. from Guadalupe y Calvo, Nelson 4848
(US). Durango: Canelas, Bolan?os 1565 (MEXU); 55?60
km SW of Durango City on road to La Flor, Breedlove
44134 (MO); from the Sierra Madre, W of Durango, Forrer
12 (UC); ca. 77 rd. km S of Durango by hwy. to La Flor,
Worthington 8826 (MO); 48 km WNW of Huejuquilla El
Alto, Jalisco to Canoas, Breedlove & Almeda 59165 (MO);
6 mi. E of Buenos Aires tow. El Salto, Straw & Forman
1795 (RSA) [83%]; 31 mi. N of Estacion Coyotes, Breed-
love 18741 (MO); 54 mi. N Estacion Coyotes, just NW of
Guachichilas, Breedlove 18783 (MO) [59%]; 71 mi. W of
Durango, E of La Campan?a, Oliver 715 (MO); 11 km SW
of La Ciudad near Buenos Aires, Breedlove 36465 (MO)
[27%]; Hwy. 40, 11.5 mi. W of La Ciudad, Wagner &
Solomon 4303 (MO); Hwy. 40, at La Campana, Reveal et
al. 2689 (MO) [74%]; Hwy. 40, about 81 mi. W of Du-
rango, Reveal & Atwood 3477 (MO) [39%]; betw. Pinos
Altos & Conchen?o, Hewitt 118 (GH) [88%]; El Salto, El
Tapextle, Tenorio & Romero 816 (MEXU); 1 km al SW de
El Salto, Tenorio & Romero 927 (MEXU); ??Arroyo de El
Salto?? al N de El Salto, Tenorio & Romero 759 (MEXU);
17 mi. W of El Salto, Waterfall 12693 (GH, US) [35%];
25 mi. E of El Salto along Mexican Hwy. 40, Breedlove
15753 (MO); 7 km W of Llano Grande, Hendrickson 1704
(RSA) [72%]; ca. 120 road mi. NW of Santiago Papa-
squiaro, Spellenberg & Zimmerman 6683 (MO, NMC); 10
Volume 14, Number 1
2004
133Wagner
Oenothera Sect. Hartmannia
mi. W of El Salto on Mazatlan rd., Straw & Gregory 1270
(RSA); Sierra Madre Occidental, 5.1 rd. mi. by hwy. 40
SW of El Salto at Arroyo de Agua, Worthington 8902
(MO); Durango, Ejido Cie?nega de Los Caballos, Ortega &
Pacheco 81 (CIIDIR, IEB, MEXU, US); Ejido, Encina,
Ortega 20 (CIIDIR, US); El Mezquital, El Zapote, Sol??s
902 (CIIDIR, US); La Guajolota, Garc??a 260 (CIIDIR, US);
Laguna del Chivo, Acevedo 445 (CIIDIR, IBUG, US); Las
Minas, Sol??s 11 (CIIDIR, US); Nombre de Dios, San Jose?
de La Parrilla, Sa?nchez 455a (US), 544 (CIIDIR, US);
Pueblo Nuevo, El Salto, Valenzuela 3?25 (CIIDIR, US);
Predio Las Bayas de la UJED, Garc??a & Acevedo 980 (US);
San Bernardino de Milpillas Chico, Sa?nchez (INI) 9 (US),
19 (CIIDIR, US); San Francisco de Lajas, I.N.I. 31 (CII-
DIR, US); Santa Ba?rbara, Garc??a 1137a (US); San Dimas,
Los Aposentos, Garc??a et al. 435 (CIIDIR, US). Guana-
juato: Guanajuato, Rinco?n del Toro, Mart??nez 760
(MEXU [2]); Can?ada de la Virgen, Agua Sabrosa, Mart??nez
935 (MEXU); 34?35 mi. E of San Luis de la Paz tow.
Xichu, Straw & Forman 1474 (MEXU, RSA). Jalisco:
14?18 km SW of Tequila on Volca?n de Tequila, Breedlove
39226 (MO) [47%]; Volca?n Tequila, Reveal & Harley 4095
(F, MEXU, MO, NY, TEX) [94%]. Michoaca?n: betw. Los
Cabras & Pueblito, Chilchota to Zacapu?, Sharp 45507
(RSA). Nayarit: 105 km WNW of Huejuquilla El Alto
along road to Jesus Maria, Breedlove 61508 (MO) [94%].
Quere?taro: Colo?n, parte alta del Cerro Zamorano, Rze-
dowski 44449 (MICH).
Acknowledgments. The holotype and the distri-
bution of isotypes of Oenothera luciae-julianiae
were kindly provided by S. Gonza?lez. Thanks are
given to Alice Tangerini for the preparation of the
three excellent plates that amply demonstrate the
distinctions among these difficult species of Oenot-
hera sect. Hartmannia. I thank Denise Mix for
comments on the manuscript, compilation of the
specimens examined, assistance with the loans, and
preparation of Figure 1. I appreciate translations of
the diagnosis of O. luciae-julianiae to Latin provid-
ed by Dan Nicolson, and the translation of the ab-
stract into Spanish by Pedro Acevedo. I greatly ap-
preciate the help of Socorro Gonza?lez in obtaining
an excellent set of collections of O. luciae-julianiae
from the region surrounding Durango, including the
type. Finally, I am grateful to Peter Hoch for his
excellent comments during the review process,
which improved the clarity and accuracy of this
paper.
Literature Cited
Alexander, M. P. 1969. Differential staining of aborted and
non-aborted pollen. Stain Technol. 44: 117?122.
Cleland, R. E. 1972. Oenothera Cytogenetics and Evolu-
tion. Academic Press, London.
Gregory, D. P. & W. M. Klein. 1960. Investigations of mei-
otic chromosomes of six genera in the Onagraceae. Ali-
so 4: 505?521.
Katinas, L., J. Crisci, W. L. Wagner & P. C. Hoch. In
press. Geographical diversification of tribes Epilobieae,
Gongylocarpeae, and Onagreae (Onagraceae) in North
America. Ann. Missouri Bot. Gard.
Levin, R. A., W. L. Wagner, P. 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. Evolutionary relationships among and within
Tribes Onagreae and Epilobieae (Onagraceae). Syst.
Bot., in press.
Loesener, L. E. T. 1913. Mexikanische und zentralameri-
kanische Novita?ten. IV. Repert. Sp. Nov. 12: 217?244.
Munz, P. A. 1932. Studies in Onagraceae VIII. The sub-
genera Hartmannia and Gauropsis of the genus Oeno-
thera. The genus Gayophytum. Amer. J. Bot. 19: 755?
778.
. 1965. Onagraceae. N. Amer. Fl. II. 5: 1?278.
Raven, P. H. 1979. A survey of reproductive biology in
Onagraceae. New Zealand J. Bot. 17: 575?593.
Rose, J. N. 1905. Studies of Mexican and Central Amer-
ican plants?No. 4. Contr. U.S. Natl. Herb. 8: 281?339.
Wagner, W. L. 1984 [1985]. Reconsideration of Oenothera
subg. Gauropsis (Onagraceae). Ann. Missouri Bot. Gard.
71: 1114?1127.
Wasmund, O. 1990. Cytogenetic investigations on Oeno-
thera nutans (Onagraceae). Pl. Syst. Evol. 169: 69?80.