Pr
s
querque
b Florida Museum of Natural History, University of Flori
c Museo de Ciencias Naturales de Panama, Panama City
a r t i c l e i n f o
Article history:
Available online xxx
Keywords:
Pearl Islands
Panama
Pleistocene
Gomphothere
Cuvieronius
. All rights reserved.
offshore from the southern coast of Panama in the eastern Pacific
Ocean (Fig. 1). The Pearl Islands fossils consist of three complete
teeth and a fourth partial tooth of gomphotheres (Proboscidea:
Gomphotheriidae). Two of the teeth were collected in nets by
Panama. Although
ronius are among
sil sites elsewhere
both from the Azuero Peninsula (Gazin, 1957; Pearson, 2005; Lucas,
2014). To our knowledge, the Pearl Islands gomphothere fossils
represent the first records of Pleistocene mammals from the con-
tinental shelf in Central America or Mexico. These teeth almost
certainly date to a glacial period, when sea levels were as much as
120 m below the present level and the shallow Gulf of Panama was
mostly dry land. The two teeth from the Pearl Islands with the best* Corresponding author.
Contents lists available at ScienceDirect
Quaternary In
.e l
Quaternary International xxx (2015) 1e14E-mail address: gary.morgan1@state.nm.us (G.S. Morgan).the continental shelf in the vicinity of the Pearl Islands (Archi-
pi
elago de las Perlas) in the Gulf of Panama (Golfo de Panam
a),
in Central America (Cisneros, 2005; Lucas and Alvarado, 2010), only
two records of Cuvieronius were known previously from Panama,© 2015 Elsevier Ltd and INQUA
1. Introduction
We report four proboscidean teeth of Late Quaternary age from
fisherman from the shallow waters of the Gulf of
proboscideans of the gomphothere genus Cuvie
themost commonmammals from Pleistocene fosfirst record of late Pleistocene fossils of terrestrial mammals from the continental shelf in Central
America.http://dx.doi.org/10.1016/j.quaint.2015.11.003
1040-6182/© 2015 Elsevier Ltd and INQUA. All rights
Please cite this article in press as: Morgan
continental shelf, Pearl Islands, Panama, Quda, Gainesville, FL 32611, USA
, Panama
a b s t r a c t
Fishermen have recovered four Quaternary proboscidean teeth from the continental shelf in the vicinity
of the Pearl Islands, about 50e80 km offshore from the southern coast of Panama. Two upper third
molars (M3) and one lower third molar (m3) are similar to comparable teeth of the Pleistocene gom-
phothere Cuvieronius based on the presence of 4½ to 5½ lophs/lophids that are either horizontal or
slightly inclined to long axis of the tooth and rather complicated enamel with single trefoils, incipient
double trefoils, and numerous small accessory cusps. Cuvieronius is also known from the Pleistocene El
Hatillo and La Trinidaíta sites from the Azuero Peninsula in Panama. The teeth of Cuvieronius from the
Pearl Islands are referred to C. hyodon following recent taxonomic revisions indicating a single pan-
American species of this genus was present in both North America and South America. The oldest re-
cords of Cuvieronius are from early Pleistocene (early Irvingtonian) faunas in El Salvador, Florida, and
New Mexico. Cuvieronius dispersed to South America in the early Pleistocene during the Great American
Biotic Interchange, with the earliest record of C. hyodon on that continent from the early to middle
Pleistocene (Ensenadan) Tarija fauna in Bolivia. The two late Pleistocene populations of C. hyodon in the
Neotropical region have a disjunct biogeographic distribution, with the population from southern Mexico
and Central America separated from the second population in the Andean highlands of Ecuador, Peru,
and Bolivia by a distance of about 1000 km. The intervening region comprising the lowland tropics of
northern South America was populated by the gomphothere Notiomastodon during the late Pleistocene,
although Notiomastodon is also known from Andean localities in Ecuador and Peru. Two of the Cuvier-
onius teeth from the Pearl Islands were recovered in nets by shrimp fisherman from depths of about
90 m, likely indicating they date to the Last Glacial Maximum between 30 and 15 ka, when sea level was
as much as 120 m lower than present and the Gulf of Panama was dry land. These teeth represent thea New Mexico Museum of Natural History, Albu , NM 87104, USAGary S. Morgan a, *, Bruce J. MacFadden b, Martín Martínez cForum communication
Quaternary gomphotheres (Mammalia:
Gomphotheriidae) from the continental
journal homepage: wwwreserved.
, G.S., et al., Quaternary go
aternary International (2015)oboscidea:
helf, Pearl Islands, Panama
ternational
sevier .com/locate/quaintmphotheres (Mammalia: Proboscidea: Gomphotheriidae) from the
, http://dx.doi.org/10.1016/j.quaint.2015.11.003
ry InG.S. Morgan et al. / Quaterna2provenance were recovered from a depth of about 90 m, suggesting
they date to the late Pleistocene, probably during the Last Glacial
Maximum between 30 and 15 ka. We provide descriptions and
measurements of Pearl Islands gomphothere teeth, compare them
to other gomphotheres from Central America, Mexico, Texas, Flor-
ida, and South America, and discuss their taxonomy, biogeography
and provenance.
2. Materials and methods
The four teeth of gomphotheres from the vicinity of the Pearl
Islands are housed in three museums. Two teeth are on display in
the Museo de Ciencias Naturales, Panama City, Panama (MCNP);
one tooth is on display in the Biomuseo, Panama City, Panama, but
is originally from the paleontology collection of the Smithsonian
Tropical Research Institute, Center for Tropical Paleontology and
Archaeology (STRI/CTPA); and one tooth is in the vertebrate pale-
ontology collection of the U. S. National Museum of Natural History
(USNM), Smithsonian Institution, Washington, DC. We also exam-
ined comparative specimens of Cuvieronius in the vertebrate pale-
ontology collection of the Florida Museum of Natural History at the
University of Florida (UF) in Gainesville.
In addition to the museum acronyms listed above, other ab-
breviations used in this paper are: ka (kilo-anna ¼ thousands of
years); Ma (Mega-anna ¼ millions of years); GABI (Great American
Fig. 1. Map of Panama showing the location of late Pleistocene sites containing the gomphot
2. El Hatillo. Sites 3e5 are in the Gulf of Panama in the vicinity of the Pearl Islands. Site 3. 8 k
Jos
e. Site 4. Near Isla de San Jos
e. Site 5. South of Isla del Rey. The break in slope at the bo
Please cite this article in press as: Morgan, G.S., et al., Quaternary go
continental shelf, Pearl Islands, Panama, Quaternary International (2015)ternational xxx (2015) 1e14Biotic Interchange); LF (Local Fauna); LGM (Last Glacial Maximum);
NALMA (North American land mammal age); SALMA (South
American land mammal age). The abbreviations for tooth positions
are standard for mammals, with upper case letters for upper teeth
and lower case letters for lower teeth. For example, M3 is an upper
third molar and m2 is a lower second molar. Descriptions of the
teeth follow the dental terminology for gomphotheriid pro-
boscideans (Savage, 1955; Tobien, 1973; Lambert, 2007). In dis-
cussing gomphotheres from Mexico and Central America, we use
the geographic names Mesoamerica, Middle America, and tropical
North America interchangeably to refer to this geographic region.
We prefer the term “gomphothere” for members of the probosci-
dean family Gomphotheriidae, rather than the terms “mastodon”
or “mastodont” which are used for members of both the Gom-
photheriidae and Mammutidae. We restrict usage of mastodon to
the Mammutidae, including the American mastodon Mammut
americanum.
We follow current usage in recognizing the Pliocene/Pleistocene
boundary at 2.58 Ma, corresponding to the onset of Northern
Hemisphere glaciation and the boundary between the Gauss and
Matuyama geomagnetic chrons (Gibbard et al., 2010). The ages,
boundaries, and faunal characterizations of the Pliocene and
Pleistocene land mammal ages follow Bell et al. (2004) for the
Blancan, Irvingtonian, and Rancholabrean NALMA in North America
and Marshall et al. (1984) and Cione and Tonni (1995) for the
here Cuvieronius hyodon. Sites 1e2 are on the Azuero Peninsula. Site 1. La Trinidaíta. Site
m west of Isla de Pedro Gonz
alez (abbreviated P. G.) and 10 km northwest of Isla de San
ttom of the map indicates the edge of the continental slope at about 200 m depth.
mphotheres (Mammalia: Proboscidea: Gomphotheriidae) from the
, http://dx.doi.org/10.1016/j.quaint.2015.11.003
ry InUquian (¼ Marplatan), Ensenadan, and Lujanian SALMA in South
America.
3. Regional setting
Three complete teeth and one partial tooth of gomphotheres are
reported from the shallow waters of the Gulf of Panama near the
Archipi
elago de las Perlas or Pearl Islands, about 75e100 km
southeast of Panama City, Panama (Fig. 1). Based on the available
provenance, all four teeth are derived from the continental shelf
from depths as great as 90 m. At least two of teeth, and probably all
four teeth, were found by fishermen in shrimp nets that were
dragged along the sea floor. For the two teeth known to have been
caught in fisherman's nets, the depths should be considered ap-
proximations since we do not know the exact distances or depths
over which the nets were dragged. Not surprisingly, considering the
conditions of their discovery, these specimens have imprecise lo-
calities and lack geological data or other associated faunal remains.
One tooth was found south of Isla del Rey, the largest of the Pearl
Islands, two teeth were found near Isla de San Jos
e, and a fourth
tooth was found west of Isla de San Jos
e and Isla de Pedro Gonz
alez
(Fig. 1). The area of the Pearl Islands and continental shelf cir-
cumscribed by the localities for these fossils is between approxi-
mately 8100 and 8210 North latitude and 78400 and 79120 West
longitude. These sites range from 50 to 80 km offshore from the
southern coast of Panama. The latitude of the Pearl Islands pro-
boscidean teeth would make them among the southernmost
Quaternary fossils known from Central America. Specimens of
Cuvieronius and other mammals from Late Quaternary sites on the
Azuero Peninsula of Panama were found slightly farther south,
between 7 and 8 North latitude, about 200 km southwest of the
Pearl Islands (Gazin, 1957; Lucas, 2014).
3.1. Previous records of Quaternary proboscideans from Panama
There are three published records of Pleistocene proboscideans
from Panama. Gazin (1957) described the giant ground sloth Ere-
motherium from the El Hatillo site (Fig. 1, site 2), located about 2 km
west of Pes
e in Herrera Province on the Azuero Peninsula in south-
central Panama (7550 N, 80380 W), and also discussed an associ-
ated vertebrate fauna of about 10 species, including a proboscidean.
Gazin (1957) tentatively identified the El Hatillo proboscidean as
Cuvieronius hyodon, recognized at that time as a South American
species. Pearson (2005) identified a tooth fragment, three verte-
brae, and tibia of Cuvieronius from the La Trinidaíta site (Fig. 1, site
1), located just west of El Hatillo about 9 km west of Pes
e (7540 N,
80420 W). Pearson referred the gomphothere material from La
Trinidaíta to C. tropicus, generally recognized as the North American
species of Cuvieronius (see taxonomic discussion below). Lucas
(2014) reexamined the late Pleistocene mammalian fauna from El
Hatillo. He described and illustrated the gomphothere teeth pre-
viously mentioned by Gazin (1957), referring these specimens to C.
hyodon. The El Hatillo and La Trinidaíta sites are located at an
elevation of about 100 m on the Azuero Peninsula about 30 km
inland from the Bahía de Parita, a bay in the western Gulf of Pan-
ama. Brief descriptions of the gomphotheres from El Hatillo and La
Trinidaíta are presented below, after the description of the
Cuvieronius teeth from the Pearl Islands.
3.2. Pearl Islands gomphothere localities
The Pearl Islands proboscidean tooth with the most complete
data is a right M3 (USNM 421665), dredged from a depth of 50
fathoms (about 300 feet or 90m) by a shrimp trawler belonging to a
G.S. Morgan et al. / QuaternaMr. Earnist. A cast of this tooth was donated to the U. S. National
Please cite this article in press as: Morgan, G.S., et al., Quaternary go
continental shelf, Pearl Islands, Panama, Quaternary International (2015)Museum of Natural History through Robert N. Stewart, formerly a
geologist with the U. S. Panama Canal Zone. Although the locality
data with the specimen state that the tooth was found “… south of
the Pearl Islands of Panama” the coordinates associated with the
fossil (8210 North latitude, 79120 West longitude) place the lo-
cality on the continental shelf just west of the Pearl Islands, about
8 kmwest of Isla de Pedro Gonz
alez and 10 km northwest of Isla de
San Jos
e (Fig. 1, site 3).
Two teeth on display in the Museo de Ciencias Naturales, Pan-
ama City, Panama (MCNP 1 and MCNP 2) were collected by J. V.
Delgado from “Isla de San Jos
e, Archipi
elago de las Perlas” accord-
ing to the specimen label associated with these teeth (Fig. 1, site 4).
Although the locality information does not specify that the fossils
were recovered by fisherman, the two MCNP teeth from Isla de San
Jos
e were collected underwater in a marine environment based on
the presence of marine epiphytic invertebrates adhering to the
ventral surface of each tooth, including oysters, gastropods, small
solitary corals, and bryozoans. The occurrence of the marine epi-
phytes only on the ventral or underside of the tooth (the roots are
broken away) suggests that the teeth were both resting with the
occlusal or crown surface facing down on the sea floor. The teeth
are a grayish black in color and are heavily mineralized, whereas
the attached invertebrates are white and appear to be modern, not
fossil.
A fourth gomphothere tooth from the Pearl Islands, a right m3,
was originally donated to the collection of Smithsonian Tropical
Research Institute/Center for Tropical Paleontology and Archae-
ology (STRI/CTPA) in Panama in about 2008. The tooth is now on
display in the recently opened Biomuseo in Panama City, Panama.
On the basis of information provided by the collector to Richard
Cooke, an anthropologist with STRI/CTPA, the tooth was recovered
by the captain of a shrimp boat trawling in about 50 fathoms of
water south of Isla del Rey (Fig. 1, site 5). This is about the same
depth (about 300 feet or 90 m) fromwhich the tooth west of Isla de
Pedro Gonz
alez and Isla de San Jos
e was recovered.
4. Results
4.1. Descriptions of gomphothere teeth from Panama
4.1.1. Right m3 from Isla del Rey, STRI/CTPA Collection (now on
display in the Biomuseo)
A right m3 from south of Isla del Rey in the Pearl Islands, orig-
inally in the STRI/CTPA Collection (STRI/CTPA 1) and now on display
in the Biomuseo, is very well preserved with an intact crown, but
with the roots broken off (Fig. 2). The fossil tooth is black in color
and heavily mineralized. It is completely unworn and lacks an
interdental wear facet on its anterior margin where the tooth
presumably would have contacted the m2. The enamel on the basal
half of the crown is highly striated or crenulated, whereas the
proximal half of each major cusp is essentially smooth. The tooth
also has numerous small to very small, rounded, accessory cusps or
cuspids distributed throughout the crown. The total number of all
major and accessory cusps on this tooth is about 60 (after Moth
e
and Avilla, 2015). Cement is absent. The tooth can be identified as
a lower m3 on the basis of the presence of more than three com-
plete lophids and the gentle labial curvature from anterior to pos-
terior. Upper M3s also have four or more lophs but are essentially
straight from anterior to posterior, not curved. As in mammalian
dental terminology in general, lower teeth have dental terms
ending in -id whereas upper teeth do not. For instance, a loph on an
upper tooth would be a lophid on a lower tooth.
The m3 has five complete lophids and several small cuspids on
the posterior edge of the tooth that could be considered a sixth
ternational xxx (2015) 1e14 3lophid, but generally are regarded as a partial or half lophid, for a
mphotheres (Mammalia: Proboscidea: Gomphotheriidae) from the
, http://dx.doi.org/10.1016/j.quaint.2015.11.003
ry InG.S. Morgan et al. / Quaterna4total of 5½ lophids. The lack of an interlophid between the fifth
lophid and the small cuspids on the posterior edge of the m3
suggests that these cuspids could also be considered the distal or
posterior cingulum, rather than a partial lophid. The four anterior
lophids extend across the entire width of the tooth and are angled
slightly posteriorly from the lingual to the labial margin. Each of
these four lophids consists of two large conical conids, one lingual,
one labial, connected at the midline by from one to three small,
rounded, accessory conulids. On each lophid, the lingual conid is
located somewhat anterior to the posterior conid. Lophid 5 is
different in size and shape from the anterior four lophids. It is much
narrower and strongly curved rather than essentially straight,
convex anteriorly, concave posteriorly. The larger lingual and labial
conids are positioned posteriorly to the two small rounded midline
conulids. Posterior to lophid 5, on the posterior margin of the tooth,
is a small half lophid consisting of four tiny cuspids that are
essentially horizontal in orientation. These cuspids could also be
considered the posterior cingulum.
Trefoiling is present on lophids 1e4, consisting of a well-
developed ridge extending posteriorly from the primary labial
cusp, just labial to the midline of the tooth. The individual trefoils
consist of two to three small rounded cuspids that would have
coalesced with wear. There is minor secondary or double trefoiling,
consisting of one or two small cuspids extending posteriorly from
the primary lingual conid. The valleys separating lophids 1e5 are
deep, extending two-thirds of the distance to the base of the crown,
interrupted only by the trefoils extending posteriorly from the
labial conid of each lophid. The valleys are not impeded by the
smaller lingual trefoils, except between lophids 4 and 5. Them3 has
several weak cingula, the most prominent of which is located along
the anterior margin of the tooth. The anterior cingulum consists of
an elliptical cuspid at the midline connected to a beaded ridge of
Fig. 2. Right m3 of Cuvieronius hyodon from south of Isla del Rey, Pear
Please cite this article in press as: Morgan, G.S., et al., Quaternary go
continental shelf, Pearl Islands, Panama, Quaternary International (2015)ternational xxx (2015) 1e14tiny cuspids that extends almost to the labial edge of the tooth. A
fairly well-developed cingulum is located on the labial edge of
lophid 4 near the base of the crown. It has an anteroposterior
orientation and consists of a beaded ridge of tiny cuspids. There is
also a very weak cingulum near the base of the crown on the labial
margin of lophid 3 that could probably be considered an anterior
extension of the better developed cingulum labial to lophid 4.
4.1.2. Right M3 and partial right m2/m3 from Isla de San Jos
e,
MCNP Collection
A right M3 from the vicinity of Isla de San Jos
e in the Pearl Islands
in theMCNPCollection (MCNP1) iswell preserved (Fig. 3). The crown
is intact but the roots have been broken off. This tooth is nearly un-
worn, except for a slight hint ofwear on the anterolabial cone on loph
1. The enamel on the proximal half of the crown is relatively smooth,
whereas the enamel is more heavily striated on the basal portion of
the crown. The tooth is a right upper M3 composed of five complete
lophs and a sixth partial loph for a total of 5½ lophs. The total number
of allmajor and accessory cusps on this tooth is about 45 (afterMoth
e
and Avilla, 2015). The first three lophs are essentially horizontal
relative to the long axis of the tooth,whereas lophs 4 and5 are angled
noticeably posteriorly from the anterolingual to the posterolabial
portion of the lophs. Although there is some variation, the four
anterior lophs consist of a large conical lingual cone and a somewhat
smaller rounded labial cone, joined at themidline by a third rounded
accessory conule that is nearly as large as the labial cone. Themidline
conule is separated from the larger lingual cone by a noticeable valley
but is more closely appressed to the labial cone of similar size, giving
an almost “twinned” appearance. Loph 5 has a large conical lingual
cone located anteriorly, separated byavalley from two small rounded
midline accessory conules that are separated by a valley from a
rounded labial cone. The labial cone is smaller than the lingual cone
l Islands, Panama (STRI/CTPA 1). A. Lingual view, B. occlusal view.
mphotheres (Mammalia: Proboscidea: Gomphotheriidae) from the
, http://dx.doi.org/10.1016/j.quaint.2015.11.003
ry InG.S. Morgan et al. / Quaternaand positioned considerably farther posteriorly. The lingual cone is
positioned progressively more anteriorly relative to the labial cone
fromthe front to thebackof the tooth, especially on lophs 4 and5. The
last half loph consists of a rather large, conicalmidline conule located
almost on the posterior margin of the tooth and a smaller rounded
conule located inamore anterolingual positionon the lingualmargin.
The valleys between the lophs are deep and wide between the
labial halves of the lophs, but are shallower and much narrower
lingually. There are small cusps located at the base of the valleys, on
the posterior surfaces of the lophs, and on the posterior margin at
the base of the crown. The primary trefoils extend posteriorly from
the large lingual cone on each loph just lingual to the midline, and
Fig. 3. Right M3 of Cuvieronius hyodon from Isla de San Jos
e, Pearl Islands, Panama (MCNP 1
showing attached specimens of modern marine invertebrates.
Please cite this article in press as: Morgan, G.S., et al., Quaternary go
continental shelf, Pearl Islands, Panama, Quaternary International (2015)ternational xxx (2015) 1e14 5consist of from one to three small cusps that are unworn. The tre-
foils are most prominent on lophs 1 and 2, weak on lophs 3 and 4,
and absent on loph 5. An anterior cingulum consisting of a low
beaded ridge composed of very small cusps extends from the base
of the primary lingual cone to the labial margin of the tooth.
A second tooth fromnear Isla de San Jos
e in theMCNP Collection
(MCNP 2) is the anterior half to two-thirds of a right m2 or m3
(Fig. 4). The posterior portion of the tooth is broken off, and thus it
is not possible to determine the exact number of lophids present or
the tooth position. The two anterior lophids are complete, the
posterior lophid or lophid 3 is broken along its posterior face. This is
the only tooth in the Pearl Islands sample that shows a substantial
). A. Occlusal view, B. ventral view, C. enlarged view of a portion of the ventral surface
mphotheres (Mammalia: Proboscidea: Gomphotheriidae) from the
, http://dx.doi.org/10.1016/j.quaint.2015.11.003
amount of wear. There is a prominent interdental wear facet on the
anterior margin of the tooth where it would have contacted the
next tooth anterior (either m1 or m2). There is a well-developed
anterior cingulum anterior to the labial portion of lophid 1, con-
sisting of a large rounded cusp anterior and ventral to the main
beaded ridge of tiny cusps. The labial edge of the tooth has
numerous small cusps at the base of the crown. The enamel of this
tooth is very thick, from 5 to 6 mm in thickness.
On each lophid the lingual conid is higher and the labial conid is
more heavily worn. Lophids 1 and 2 each have large lingual and
Fig. 4. Partial right m2/m3 of Cuvieronius hyodon from Isla de San Jos
e, Pearl Islands, Panama (MCNP 2). A. Occlusal view, B. ventral view. Note attached specimens of modern
marine invertebrates on ventral surface.
G.S. Morgan et al. / Quaternary International xxx (2015) 1e146conid and then extending to the labial margin of the tooth as a low,Fig. 5. Right M3 of Cuvieronius hyodon from near Isla de San Jos
e and Isla de Pe
Please cite this article in press as: Morgan, G.S., et al., Quaternary go
continental shelf, Pearl Islands, Panama, Quaternary International (2015)labial conids connected at the midline by two small, roundeddro Gonz
alez, Pearl Islands (USNM 421665). A. Labial view, B. occlusal view.
mphotheres (Mammalia: Proboscidea: Gomphotheriidae) from the
, http://dx.doi.org/10.1016/j.quaint.2015.11.003
having enamel developed in a spiral form.” We examined several
specimens of Cuvieronius from El Hatillo in the USNM collection,
including a lower third molar (m3), a partial tusk, an ulna, and a
tibia. The m3, cataloged under the number USNM 540665, is so
heavily worn that very little of the occlusal morphology remains;
however, this specimen clearly possesses five lophids which is
similar to the m3 from south of Isla del Rey. Measurements of the
m3 from El Hatillo are presented in Table 1. Lucas (2014) illustrated
and described the m3 of C. hyodon from El Hatillo (USNM 540665).
More informative is a partial upper tusk fromEl Hatillo that exhibits
the spiraled enamel band characteristic of Cuvieronius. From the La
Trinidaíta site, also in the Azuero Peninsula (Fig. 1, site 1), Pearson
(2005) referred a tooth fragment, complete tibia, several verte-
brae, and a proximal rib to Cuvieronius tropicus.
Table 1
Dental measurements of third upper and lower molars (M3/m3) of Cuvieronius
hyodon from the Pearl Islands, Panama, compared to measurements of teeth of
C. hyodon from Mexico, New Mexico, Texas, and Florida. The teeth from Panama,
Mexico, Texas, and Daytona Beach, Florida are Rancholabrean NALMA in age. The
specimens from Leisey Shell Pit and Punta Gorda in Florida and Tortugas Mountain
in NewMexico are early Irvingtonian NALMA. Museum acronyms are:MCNP (Museo
de Ciencias Naturales, Panama); STRI/CTPA (Smithsonian Tropical Research Institute/
Center for Tropical Paleontology and Archaeology, Panama); INAH-MRG (Instituto
Nacional de Antropologia e Historia-Museo Regional de Guadalajara, Jalisco,
Mexico); MPG (Museo de Paleontologia de Guadalajara, Jalisco, Mexico); NMMNH
(New Mexico Museum of Natural History); NMSU (New Mexico State University,
Biology Department); TMM (Texas Memorial Museum, University of Texas, Austin);
UF (Florida Museum of Natural History, University of Florida); UF/DMAS (Daytona
Museum of Arts and Sciences, specimens housed in the UF collection); USNM (U. S.
National Museum of Natural History, Smithsonian Institution). All measurements
are in mm.
Locality and tooth position Total length Maximum width
Pearl Islands, Panama
USNM 421665
right M3 182 84
MCNP 1
right M3 197 84
MCNP 2
right m2/m3 (partial) e 91
STRI/CTPA 1
right m3 201 88
El Hatillo, Panama
USNM 540665
m3 (heavily worn) 185 92
Lago Chapala, Jalisco, Mexicoa
INAH-MRG uncat.
right M3 173 85
MPG uncat
M3 201 91
INAH-MRG uncat.
right m3 198 82
INAH-MRG uncat.
right m3 202 82
MPG 5
ry International xxx (2015) 1e14 7accessory conulids of similar size. Each lophid has awell-developed
trefoil that extends posteriorly from the labial conid, just labial to
the midline. The trefoils are “club-shaped” with the rounded
portion oriented posteriorly. Lophids 2 and 3 also have smaller
anterior extensions of the trefoils on the labial conids. There is also
minor secondary or double trefoiling, consisting of single, small
rounded cusps on the posterior face of the lingual portion of
lophids 1 and 2, just lingual to the midline. These cusps would
appear as small trefoils in later wear stages. The valleys between
lophids 1 and 2 and 2 and 3 are deep both lingually and labially, but
are interrupted along the midline by the primary and secondary
trefoils.
4.1.3. Right M3 from west of Isla San Jos
e and Isla de Pedro
Gonz
alez, USNM collection
A right M3 in the U. S. National Museum of Natural History
collection, Smithsonian Institution (USNM 421665) from near Isla
San Jos
e and Isla de Pedro Gonz
alez in the Pearl Islands is complete
and virtually unworn, with just a slight amount of wear on the
labial portion of the first loph (Fig. 5). The tooth consists of four
complete lophs and a half loph at the posterior edge of the tooth for
a total of 4½ lophs. The four complete lophs, as well as the poste-
riormost half loph, are essentially horizontal to the long axis of the
tooth. Lophs 1e4 consist of a large, rounded cone lingually and an
anteroposteriorly compressed ridge composed of from three to six
smaller rounded cusps labially. The large lingual cone comprises
about 40% the width of each loph, whereas the labial ridge com-
prises the remaining 60% of thewidth. The posteriormost portion of
the M3 containing loph 5 (or half loph) is constricted transversely.
This loph is about half the width of the four anterior lophs, and
consists of two rather large, rounded cusps of similar size, one
lingual, one labial.
The enamel on the labial and lingual edges of the lophs of USNM
421665 is heavily striated or crenulated from the base of the crown
almost to the tips of the crowns. Besides the major lophs and cones,
the crown of the tooth possesses numerous tiny cusps, concen-
trated in the valleys between the lophs and on the posterior faces of
the labial portions of the lophs. The total number of all major and
accessory cusps on this tooth is about 48 (after Moth
e and Avilla,
2015). One or two small, rounded cusps extending both anteriorly
and posteriorly from the lingual cone on lophs 2e4, just lingual to
the midline, would have worn into trefoils. Loph 1 has only the
posterior portion of the trefoil, consisting of two small rounded
cusps. All four lophs have several small cusps anterior and posterior
to the labial portion of the loph, just labial to the midline, that
would have worn into small secondary or double trefoils. The val-
leys separating themajor lophs arewide and deep, interrupted only
by the primary trefoils just lingual to the midline. The M3 has two
prominent cingula, one on the anterior margin of the tooth and
another on the posterior margin. The anterior cingulum consists of
at least eight small cusps in a horizontal row that form a low,
beaded ridge at the base of the crown immediately anterior to loph
1. The posterior cingulum is composed of at least ten tiny cusps at
the base of the crown that extend from the posterolabial corner of
loph 5 around the posterior margin of the tooth to a position labial
to the anterior edge of loph 5.
4.1.4. Gomphotheres from El Hatillo and La Trinidaíta, Panama
In addition to the fossils from the Pearl Islands, there are two
other records of the gomphothere Cuvieronius from Panama. Gazin
(1957, p. 346e347) mentioned several specimens from the El
Hatillo site in the Azuero Peninsula (Fig. 1, site 2), including “…
associated skeletal portions of a single individual of the mastodon
Cuvieronius... including two badly worn last molars and sections of
G.S. Morgan et al. / Quaternatusk.” He noted that this specimen was “…characterized by tusks
Please cite this article in press as: Morgan, G.S., et al., Quaternary go
continental shelf, Pearl Islands, Panama, Quaternary International (2015)m3 199 94
MPG 712
m3 193 87
MPG 726
m3 179 82
Tortugas Mountain, New Mexicob
NMMNH 27232
right M3 211 106
NMSU 79.17.1
right m3 183 83
Ingleside, Texasc
TMM 30967-1219
right m3 218 94
Sinton, Texasd
USNM 11377
right M3 202 105
left m3 225 101(continued on next page)
mphotheres (Mammalia: Proboscidea: Gomphotheriidae) from the
, http://dx.doi.org/10.1016/j.quaint.2015.11.003
ry In4.2. Comparisons of gomphothere teeth from the Pearl Islands with
teeth of Cuvieronius from Mesoamerica, temperate North America,
and South America
Morphological comparisons among the four gomphothere teeth
from the Pearl Islands indicate that either one highly variable
species or two different species are represented. Themost revealing
comparisons are between two right M3s from near Isla San Jos
e.
These two teeth were collected in the same general area, but differ
in several important morphological characters. Both teeth are
almost totally unworn. One M3 (USNM 421665; Fig. 5) has 4½ lophs
that are essentially horizontal to the long axis of the tooth with
wide valleys between the lophs. A second M3 (MCNP 1; Fig. 3) has
5½ lophs that form an angle to the long axis of the tooth (the lingual
portion of the loph is located distinctly anterior to the labial
portion) and the valleys between the lophs are narrow especially
between the lingual cones. However, both of these M3s have a
similar number of total cusps (major cusps plus accessory cusps;
after Moth
e and Avilla, 2015), 45 in the MCNP tooth, 48 in the
USNM tooth. A lowerm3 from the Pearl Islands (STRI/CTPA 1; Fig. 2)
is similar to the MCNP M3, with 5½ angled lophids, but has a
considerably larger number of total cusps (about 60) than either of
Table 1 (continued )
Locality and tooth position Total length Maximum width
Leisey Shell Pit, Floridae
UF 129033
left M3 181 91
Punta Gorda, Floridae
UF 9741
right M3 178 87
UF 9742
left m3 192 85
UF 11230
right m3 187 87
Daytona Beach, Floridae
UF/DMAS 571
right m3 192 83
UF/DMAS 694
right m3 194 85
a Measurements from Lucas (2008b).
b Measurements from Lucas et al. (2000).
c Measurements from Lundelius (1972).
d Measurements from Hay (1926).
e Measurements from Lucas (2008a).
G.S. Morgan et al. / Quaterna8the other complete third molars from the Pearl Islands.
We compared the gomphothere teeth from the Pearl Islands
with descriptions and illustrations of upper and lower third molars
(M3/m3) of the Quaternary gomphothere Cuvieronius fromboth the
tropical and temperate regions of North America, including speci-
mens from the following localities: Río Tomayate in El Salvador
(Cisneros, 2005); Lago Chapala in the state of Jalisco, west-central
Mexico (Lucas, 2008b); the “Valley of Mexico” in central Mexico
(Cope, 1884, 1893; Osborn, 1936); Tortugas Mountain in New
Mexico (Lucas et al., 1999, 2000); Sinton and Ingleside in Texas
(Hay, 1926; Lundelius, 1972); and Leisey Shell Pit, Punta Gorda, and
Daytona Beach in Florida (Webb and Dudley, 1995; Lucas, 2008a).
Measurements of the gomphothere teeth from the Pearl Islands and
of theM3s/m3s of Cuvieronius from elsewhere in North America are
presented in Table 1. We also made comparisons between the
gomphothere teeth from the Pearl Islands and teeth of Cuvieronius
hyodon from Tarija, Boliva (Boule and Thevenin, 1920; Moth
e and
Avilla, 2015). The most common dental morphology of the M3s/
m3s among North American specimens of Cuvieronius is to have 4½
lophs/lophids, single trefoiling, and rather simple enamel with
limited development of small accessory cusps. An M3 from the
Pearl Islands (USNM 421665) closely matches the typical dental
Please cite this article in press as: Morgan, G.S., et al., Quaternary go
continental shelf, Pearl Islands, Panama, Quaternary International (2015)morphology of Cuvieronius (Fig. 5). Two other complete teeth from
the Pearl Islands, an m3 and an M3 (Figs. 2 and 3), have 5½ lophs/
lophids, incipient double trefoiling, and a somewhat more complex
enamel pattern.
Cisneros (2005) illustrated six mandibles with m3s of Cuvier-
onius from Río Tomayate, El Salvador, although he did not provide
measurements of these specimens. Cisneros described the m3s
from Río Tomayate as having 4½ to 5 angular lophids, single tre-
foiling, and simple enamel. Several of the El Salvador specimens
have a well-developed 5th lophid on m3, but none has 5½ lophids.
Cisneros also noted that several isolated upper tusks from Río
Tomayate exhibited a spiral enamel band. A sample of upper and
lower third molars of Cuvieronius from Lago Chapala, Mexico, rep-
resenting at least five individuals (Lucas, 2008b), overlap in
morphology and size with the teeth from the Pearl Islands. Most of
the specimens from Lago Chapala have 4½ lophs/lophids on M3/m3
(four complete lophs/lophids and one or two small posterior
midline cusps/cuspids constituting a ½ loph/lophid), single tre-
foiling, and a rather simple enamel pattern with limited plications.
However, one of the illustrated m3s from Lago Chapala (Lucas,
2008b, fig. 3D) is similar to the m3 from the Pearl Islands in pos-
sessing 5½ lophids. In his description of the type specimen of
Cuvieronius (¼ Dibelodon) tropicus from Mexico, a mandible with
m2em3, Cope (1884, p. 7) stated that “Reference to Von Meyer's
figure [1867] shows that the last inferior molar [m3] has five well-
developed cross-crests and a heel.” Von Meyer's illustration of the
specimen Cope later designated the type of C. tropicus was repro-
duced by Osborn (1936, fig. 513). Even though most M3s/m3s of
Cuvieronius from North America have 4½ or 5 lophs/lophids, the
type specimen of C. tropicus has 5½ lophids (“five…cross-crests and
a heel”), in agreement with anM3 and anm3 from the Pearl Islands.
Samples of Cuvieronius teeth from Pleistocene sites in temperate
North America, including New Mexico, Texas, and Florida, exhibit
the same general dental morphology as described above for
Cuvieronius from Mexico and Central America, including the teeth
from the Pearl Islands. As with the Mesoamerican Cuvieronius,
there is considerable dental variation in the temperate North
American sample. Specimens of Cuvieronius from the early Pleis-
tocene (early Irvingtonian) Tortugas Mountain Fauna in New
Mexico include a palate with two M3s having 4 lophs and a single
posterior midline cusp and a lower jaw from a different individual
with an m3 that has four lophids and two well-developed cuspids
on the posterior margin that could be interpreted as an incipient
5th lophid or half lophid, or as a posterior cingulum (Lucas et al.,
1999, 2000). An associated maxilla and mandibles of Cuvieronius
from the late Pleistocene (Rancholabrean) Sinton Local Fauna (LF)
in southern Texas have 5½ lophs/lophids on theM3/m3 (Hay,1926).
An isolated m3 of Cuvieronius from the Rancholabrean Ingleside LF
in southern Texas also has 5½ lophids (Lundelius, 1972). The
Cuvieronius teeth from Texas closely resemble the M3 and m3 from
the Pearl Islands with 5½ lophs/lophids. The Florida sample of
Cuvieronius includes isolated M3s from the early Irvingtonian Lei-
sey Shell Pit and Punta Gorda LFs and twomandibles withm3s from
the Rancholabrean Daytona Beach LF. The M3s from Leisey and
Punta Gorda have four lophs with a small midline cusp on the
posterior midline and the two m3s from Daytona Beach have four
lophids with a fifth (half) lophid posteriorly consisting of two small
cusps. The M3s of Cuvieronius from Leisey and Punta Gorda are
similar to the simpler of the two M3s from the Pearl Islands (USNM
421665).
We also made comparisons of the gomphothere teeth from the
Pearl Islands with a large sample of Cuvieronius teeth from the early
to middle Pleistocene (Ensenadan SALMA) fauna from Tarija,
Bolivia, based on illustrations and descriptions of the Bolivian
ternational xxx (2015) 1e14sample in Boule and Thevenin (1920) and Moth
e and Avilla (2015),
mphotheres (Mammalia: Proboscidea: Gomphotheriidae) from the
, http://dx.doi.org/10.1016/j.quaint.2015.11.003
ry Inas well as specimens from Tarija in the UF/FLMNH collection. Moth
e
and Avilla (2015) illustrated two lower m3s of C. hyodon from Tarija,
one with a simple enamel pattern and one with a complex enamel
pattern. These two teeth encompass much of the dental variation
observed in Cuvieronius teeth from the Pearl Islands, elsewhere in
Central America, Mexico, and temperate North America. The Tarija
teeth have 4½ to 5 lophids and range from a very simple enamel
pattern with little development of accessory cusps to a more
complex pattern with numerous accessory cusps.
Moth
e and Avilla (2015) proposed a method for evaluating the
enamel complexity of the third molars (M3/m3) of South American
gomphotheres by counting the total number of cusps, including
both major cusps and accessory cusps. They determined that the
third molars of South American Cuvieronius have between 33 and
60 total cusps, with most specimens ranging from 40 to 53. Two
complete upper thirdmolars (M3s) of gomphotheres from the Pearl
Islands are within the average range of total cusps for Cuvieronius
third molars from South America, with 45 cusps in MCNP 1 and 48
in UNSM 421665. The other complete third molar from the Pearl
Islands, a lower m3 (STRI/CTPA 1), has considerably more complex
enamel, with about 60 total cusps (ranging from 58 to 65 cusps,
depending on whether or not the tiniest accessory cusps are
counted). The m3 from the Pearl Islands agrees more closely with
the total cusp count for Notiomastodon third molars from South
America, which have between 35 and 82 total cusps, with most
specimens ranging from 46 to 58. However, Moth
e and Avilla
(2015) noted there is considerable overlap in total cusp count be-
tween Cuvieronius and Notiomastodon and, with the exception of
extremely complex teeth of Notiomastodon, the number of cusps on
the last molars is not valid to differentiate these two genera.
Lambert and Shoshani (1998) observed that North American
samples of Cuvieronius exhibit a remarkable range of variation in
cheek tooth morphology, including four and a fraction to five and a
fraction lophs, single to double trefoiling, and ptychodont enamel
(numerous small accessory cusps, often with highly striated
enamel) to simple aptychodont enamel. Much of the range of
dental variation in the Cuvieronius teeth from Central America,
Mexico, New Mexico, Texas, and Florida, as well as Tarija, Bolivia,
can be duplicated in the small sample of teeth from the Pearl
Islands. Overall, there is substantial variation in dental features
both within and between North American samples of Cuvieronius.
Measurements in Table 1 indicate that the Cuvieronius teeth from
the Pearl Islands fall within the observed size range for the majority
of Cuvieronius third molars from North America. There are several
notably large M3s/m3s in the North American sample, including
specimens from the early Irvingtonian Tortugas Mountain Fauna in
New Mexico and the Rancholabrean Ingleside and Sinton LFs in
Texas (Table 1). Despite the considerable range of variation in
dental morphology observed in the Pearl Islands teeth, we tenta-
tively refer all of these specimens to Cuvieronius hyodon, the com-
mon late Pleistocene gomphothere species from Central America.
See taxonomic discussion below for our usage of C. hyodon rather
than C. tropicus for North American Cuvieronius.
4.3. Age of Cuvieronius from the Pearl Islands
We did not attempt to obtain a radiocarbon date on the teeth
from the Pearl Islands because all of the specimens have been
submersed in saltwater for a long period of time, probably since the
end of the Pleistocene, if not earlier. According to Ron Hatfield from
Beta Analytic (in litt. October 8, 2013), “Tooth proteins can be
leached away if submersed in water for long periods of time. Given
the very long time that these samples were submerged it's likely
that any tooth proteins have been removed.” No other mammal
G.S. Morgan et al. / Quaternafossils have been found in association with the Cuvieronius teeth
Please cite this article in press as: Morgan, G.S., et al., Quaternary go
continental shelf, Pearl Islands, Panama, Quaternary International (2015)from the Pearl Islands that might provide additional information on
their biochronology. The identification of the teeth as Cuvieronius
restricts their age to between the early Irvingtonian and late Ran-
cholabrean (~1.6 Mae10 ka). As discussed below, most records of
Cuvieronius from Central America are late Pleistocene in age, with
the exception of two early Pleistocene faunas from El Salvador
(Webb and Perrigo, 1984; Cisneros, 2005).
The most useful information on the age of the Cuvieronius teeth
from the Pearl Islands comes from their provenance. All four of the
teeth were found in a marine environment, and the two specimens
with the most complete data were recovered in shrimp nets from a
depth of approximately 50 fathoms (¼ 300 feet ¼ ~90m). All four of
the teeth are in excellent condition, although lacking roots, sug-
gesting that they were not transported a long distance and were
probably buried for a considerable period of time and not subjected
to movement by tides or currents. Two of the teeth have attached
specimens of modern epiphytic marine invertebrates (see Figs. 3B,
C, 4B), indicating that the specimens rested on the sea floor for at
least a short period of time, although not long enough to have
suffered much damage. If the teeth were not transported a long
distance from where they were recovered on the sea floor in the
Gulf of Panama, then the depth at which they were found (~90 m)
should give a good indication of sea level at the time the fossils
were deposited, considering that the continental shelf must have
been dry land for the gomphotheres to have survived there.
Precise data pertaining to Pleistocene sea levels are only avail-
able for about the past 130 ka, covering the last glacialeinterglacial
cycle or Marine Isotope Stages (MIS) 1e5 (Lambeck et al., 2002).
According to several proxies of sea level change, including uplifted
coral reefs with uranium-series dates, estimated ice volumes, and
oxygen (18O/16O) isotopes from marine microfossils, at only one
time in the last 130 ka, during the Last Glacial Maximum (LGM)
between about 30 and 15 ka (MIS 2), were sea levels as low as 90 m
below current mean sea level (msl) (Lambeck et al., 2002). Sea level
reached its lowest level (~120 m below msl) near the end of the
LGM about 19 ka; however, sea level remained approximately 90 m
below msl until about 15 ka (Lambeck et al., 2002). We strongly
suspect that the Pearl Islands gomphothere teeth date to the LGM
or the latest Pleistocene (late Rancholabrean NALMA), probably
between 30 and 15 ka, based on the recovery of two of the teeth
from depths of approximately 90 m on the continental shelf in the
Gulf of Panama.
5. Discussion
5.1. Taxonomy and systematics of Cuvieronius
The species-level taxonomy of Cuvieronius in both North
America and South America is complex and confusing. Several
comprehensive works on North American Pleistocene Proboscidea
have identified Cuvieronius only to the generic level (e.g., Kurt
en
and Anderson, 1980; Lambert and Shoshani, 1998). Arroyo-
Cabrales et al. (2007) noted that three different species names
have been applied to this genus in Mesoamerica, C. hyodon,
C. oligobunis, and C. tropicus. Webb and Dudley (1995) used the
oldest available name for a North American species of Cuvieronius,
C. tropicus (Cope, 1884), for specimens from the early Pleistocene
Leisey Shell Pit and Punta Gorda faunas in Florida. C. tropicus was
originally named for a lower jaw from the state of Michoacan in the
Valley of Mexico, central Mexico, presumably of late Pleistocene age
(Cope, 1884). Cope (1893) later named a second species, C. oligo-
bunis, based on a pair of lower jaws from the late Pleistocene
Tequixquiac fauna, also from the Valley of Mexico in central Mexico.
Webb and Dudley (1995) synonymized C. oligobunis with
ternational xxx (2015) 1e14 9C. tropicus. Most recent authors (e.g., Ferretti, 2008; Moth
e et al.,
mphotheres (Mammalia: Proboscidea: Gomphotheriidae) from the
, http://dx.doi.org/10.1016/j.quaint.2015.11.003
ry In2013) recognize a single species of Cuvieronius from South America,
C. hyodon (Fischer, 1814), the oldest available name for a South
American species in this genus.
Until recently, the trend has been to recognize two species of
Cuvieronius, C. tropicus from North America and C. hyodon from
South America. However, the range of dental variation in samples of
C. tropicus and C. hyodon appears to overlap substantially (Lucas,
2008a; Lucas and Alvarado, 2010). In comparisons of Cuvieronius
teeth from Florida, Mexico, Central America, and South America,
Lucas (2008a) could find no consistent differences in the dentition,
size, or other characters to separate North American Cuvieronius,
previously referred to C. tropicus, and South American populations
of Cuvieronius referred to C. hyodon. The similarity between these
two species led Lucas (2008a, 2013) and Lucas and Alvarado (2010)
to refer all Cuvieronius from temperate North America and Meso-
america to C. hyodon (Fischer, 1814), which has priority over
C. tropicus (Cope, 1884).
Pending a detailed taxonomic review of all New World Cuvier-
onius, we recognize a single pan-American species in this genus,
C. hyodon. A similar situation occurs in late Pleistocene populations
of the giant ground sloth Eremotherium, which had been split into
North American (E. mirabile) and South American (E. laurillardi)
species, until Cartelle and de Iuliis (1995) combined them as the
pan-American species E. laurillardi. Cuvieronius and Eremotherium
are often associated in Central American Pleistocene faunas,
including Panamawhere these two genera co-occur in the El Hatillo
and El Trinidaíta sites (Gazin, 1957; Pearson, 2005; Lucas, 2014).
Cisneros (2005) noted the abundance of Cuvieronius in the Irving-
tonian Río Tomayate fauna in El Salvador, where at least six in-
dividuals occur, together with a skeleton of Eremotherium.
Cuvieronius and Eremotherium are two of the most common large
mammals in the Rancholabrean Daytona Beach fauna along the
Atlantic coast of Florida (Morgan and Hulbert, 1995).
Cuvieronius and another gomphothere genus, Rhynchotherium,
appear to be closely related based on the presence of the derived
character of the helicoidal (spiral) curvature of the upper tusks,
including the enamel band (Lambert and Shoshani, 1998; Lucas and
Morgan, 2008). These two genera can be easily distinguished from
the morphology of the mandibles. Cuvieronius has a short (brevir-
ostrine) mandibular symphysis and lacks lower tusks, whereas
Rhynchotherium has a longer symphysis that is downturned at a 45
angle or greater and bears a pair of small lower tusks that are
rounded to elliptical in cross-section and often have a lateral
enamel band. Webb and Perrigo (1984) recommended that the
presence (Rhynchotherium) or absence (Cuvieronius) of lower tusks
be used as the defining character separating these two genera. In
addition, Rhynchotherium has third molars with only 4 or at most
4½ lophs/lophids and rather simple enamel, whereas Cuvieronius
tends to have more complicated teeth with third molars having 4½
to 5½ lophs/lophids and enamel with some development of
accessory cusps. Several late Miocene (Hemphillian NALMA) gom-
phothere species from Mexico and Central America previously
referred to Rhynchotherium, R. blicki (including Aybelodon hondur-
ensis) and R. tlascalae (Webb and Perrigo,1984), are now considered
to be advanced species of Gomphotherium (Tobien, 1973; Lucas and
Morgan, 2008).
5.2. Biochronology of Cuvieronius
Despite references to the contrary (e.g., Kurt
en and Anderson,
1980; Webb and Dudley, 1995), there is no credible evidence for
the occurrence of Cuvieronius in North America prior to the
beginning of the Irvingtonian (about 1.6 Ma). Among specimens
that possess the symphyseal region of the lower jaws revealing the
G.S. Morgan et al. / Quaterna10presence or absence of lower tusks, Rhynchotherium occurs only in
Please cite this article in press as: Morgan, G.S., et al., Quaternary go
continental shelf, Pearl Islands, Panama, Quaternary International (2015)late Hemphillian and Blancan faunas, becoming extinct in the latest
Blancan at about 2.2 Ma (Lucas and Morgan, 2008), whereas
Cuvieronius is restricted to early Irvingtonian and younger faunas,
becoming extinct at the end of the Rancholabrean with the
remainder of the Pleistocene megafauna. Specimens previously
referred to Cuvieronius from Blancan faunas consist of isolated teeth
or mandibles that lack the symphysis, and thus their identification
cannot be confirmed. The non-overlapping biochronologic ranges
of Rhynchotherium and Cuvieronius suggest an ances-
toredescendant relationship between the two genera. Cuvieronius
apparently evolved from Rhynchotherium in the late Blancan, with
the anterior shortening of the mandibles and loss of the lower
tusks. There is currently no evidence for this evolutionary transi-
tion in late Blancan faunas from temperate North America. All late
Blancan specimens of this lineage that preserve the symphysis are
referable to Rhynchotherium. Although Webb and Dudley (1995, p.
648) mentioned that “An early plesiomorphous (or transitional)
form of Cuvieronius occurs in the late Blancan of Florida, e.g., at
Macasphalt Pit in Sarasota Co., Florida…” an examination of the
mandibles from the late Blancan Macasphalt Shell Pit, upon which
their observation was based, confirms the identification of this
specimen as Rhynchotherium not Cuvieronius. The lack of evidence
for Cuvieronius in temperate North American Blancan faunas sug-
gests that the evolution of this genus may have occurred in Mes-
oamerica where late Blancan faunas are scarce (Mexico) or absent
(Central America). During the early Pleistocene, Cuvieronius
dispersed across the Panamanian Isthmus and entered South
America as a participant in the GABI (Lucas, 2013).
Cuvieronius occurs in early through late Pleistocene faunas
(Irvingtonian and Rancholabrean NALMAs) in North America,
including Central America, and early through late Pleistocene
faunas (Ensenadan and Lujanian South American land mammal
ageseSALMAs) in South America. The oldest confirmed specimens
of Cuvieronius hyodon are early Pleistocene (early Irvingtonian,
~1.6e1.0 Ma) records from North America, including the Leisey
Shell Pit and Punta Gorda faunas from Florida (Webb and Dudley,
1995; Lucas, 2008a), the Tortugas Mountain fauna from New
Mexico (Lucas et al., 1999; Morgan and Lucas, 2003), and the Bar-
ranco del Sisimico and Río Tomayate faunas from El Salvador (Webb
and Perrigo, 1984; Cisneros, 2005). Other Irvingtonian records of
Cuvieronius from New Mexico, Texas, Florida, and North Carolina
consist of less diagnostic fossils that probably are not identifiable to
the species level (Hibbard and Dalquest, 1966; Morgan and Hulbert,
1995; Sanders, 2002; Morgan and Lucas, 2003). Records of Cuvier-
onius from late Pleistocene (Rancholabrean) sites in temperate
North America are not as widespread as in the Irvingtonian, with
the most complete Rancholabrean specimens from Daytona Beach
on the Atlantic Coast of Florida (Morgan and Hulbert, 1995) and
Sinton and Ingleside on the Gulf Coast of southern Texas (Hay,1926;
Lundelius, 1972). Most records of Cuvieronius from Central America
and Mexico appear to be late Pleistocene, although the age of many
Mesoamerican proboscidean sites is problematic (Arroyo-Cabrales
et al., 2007; Lucas and Alvarado, 2010).
The earliest well-dated specimens of Cuvieronius hyodon in
South America are from Tarija, Bolivia (Ferretti, 2008; Moth
e et al.,
2013). Recent studies of the geochronology and biostratigraphy of
the Tarija Fauna confirm an age range of 0.99 to 0.76 Ma, corre-
sponding to a late early tomiddle Pleistocene age and referral to the
Ensenadan SALMA (MacFadden, 2013; MacFadden et al., 2013).
5.3. Biogeography of Cuvieronius
Cuvieronius is the most common proboscidean in late Pleisto-
cene deposits in tropical regions of North America, including
ternational xxx (2015) 1e14southern Mexico and Central America from Guatemala south to
mphotheres (Mammalia: Proboscidea: Gomphotheriidae) from the
, http://dx.doi.org/10.1016/j.quaint.2015.11.003
ry InPanama (Arroyo-Cabrales et al., 2007; Lucas and Alvarado, 2010).
Cuvieronius also is known from two early Pleistocene faunas in
Mesoamerica, Barranca del Sisimico and Río Tomayate in El Salva-
dor (Webb and Perrigo, 1984; Cisneros, 2005). Cuvieronius is un-
common in the temperate portion of North America, with a rather
restricted geographic distribution in the southern United States and
northern Mexico. The northernmost occurrences of Cuvieronius in
the Irvingtonian are from New Mexico, Texas, Florida, and North
Carolina (Webb and Dudley, 1995; Lucas et al., 1999, 2000; Sanders,
2002; Lucas, 2008a). Records of Cuvieronius from two early
Irvingtonian faunas from the Rio Grande valley in southern New
Mexico at about 1200 m are among the highest elevation records of
this genus in North America (Lucas et al., 1999, 2000). Cuvieronius
disappears from the American Southwest in the early Irvingtonian
about a million years ago (Lucas et al., 1999), presumably related to
the increasingly cooler and drier climate. The northern distribution
of Cuvieronius during the Rancholabrean was restricted to the Gulf
and Atlantic coastal plains of the southeastern United States, with
records from Texas, Florida, and South Carolina (Hay, 1926;
Lundelius, 1972; Sanders, 2002; Baskin and Thomas, 2007; Lucas,
2008a).
General patterns of Pleistocene proboscidean abundance and
distribution in tropical North America reveal some interesting
trends. Among the three genera of late Pleistocene proboscideans
known from Mexico and Central America (Cuvieronius, Mammut,
and Mammuthus), the mastodon Mammut is the rarest with 15 re-
cords from northern and central Mexico and a single record from
Honduras (Arroyo-Cabrales et al., 2007; Lucas and Alvarado, 2010).
The mammoth Mammuthus is the most abundant proboscidean in
northern and central Mexico, but was uncommon in southern
Mexico (Arroyo-Cabrales et al., 2007). Mammoths are even rarer in
Central America where there are fewer than ten records, with the
southernmost occurrence in northwestern Costa Rica (Lucas et al.,
1997; Lucas and Alvarado, 2010). Cuvieronius was rare in the
northern half ofMexico, but was themost commonproboscidean in
late Pleistocene faunas in southern Mexico and Central America
(Arroyo-Cabrales et al., 2007; Lucas and Alvarado, 2010). In
southern Central America south of 10 North latitude, including
central and eastern Costa Rica and Panama, Cuvieronius is the only
known Pleistocene proboscidean (Gazin, 1957; Pearson, 2005;
Lucas and Alvarado, 2010; Lucas, 2014).
Overall abundance patterns in North America during the late
Pleistocene reveal that Mammut is the most common proboscidean
in the more heavily forested eastern half of the continent, Mam-
muthus is most abundant in the western grasslands, and Cuvier-
onius is the dominant proboscidean of the savannas and tropical
forests of southern Mexico and Central America. Mesoamerican
records of Cuvieronius are found in both lowland and upland sites,
but are more common in the lowlands, including the specimens
reported here from the Panamanian continental shelf in the vicinity
of the Pearl Islands. Despite their differing biogeographic patterns,
these three genera do not have mutually exclusive distributions.
Mammut and Mammuthus are found together in many late Pleis-
tocene sites in temperate North America and Cuvieronius and
Mammuthus are often associated in sites in the southern United
States and Mexico. Arroyo-Cabrales et al. (2007) stated that
Cuvieronius and Mammut have an ecologically parapatric distribu-
tion in Mexico. Although a rare association, Cuvieronius and Mam-
mut are known to co-occur in several Rancholabrean sites in
temperate North America, including Daytona Beach in Florida
where these two genera are found with Mammuthus (Morgan and
Hulbert, 1995). Cuvieronius, Mammut, and Mammuthus are also
associated in the Rancholabrean Ingleside and Nueces River faunas
on the Gulf Coastal Plain of southern Texas (Lundelius, 1972; Baskin
G.S. Morgan et al. / Quaternaand Thomas, 2007).
Please cite this article in press as: Morgan, G.S., et al., Quaternary go
continental shelf, Pearl Islands, Panama, Quaternary International (2015)North American proboscidean distributional patterns were
somewhat different during the early Pleistocene. Cuvieronius is
more common than Mammut in Florida early Irvingtonian faunas,
where Cuvieronius often occurs in association with Mammuthus,
including Leisey Shell Pit and Punta Gorda (Morgan and Hulbert,
1995; Webb and Dudley, 1995). Rancholabrean records of Mam-
mut in the southeastern United States far outnumber Cuvieronius,
perhaps suggesting a change to more temperate forests after the
Irvingtonian. The abundance and distribution of proboscideans in
Mesoamerica during the Irvingtonian is poorly known because of
the paucity of faunas of this age, although the largest reported
sample of Cuvieronius from North America occurs in the early
Irvingtonian Río Tomayate LF in El Salvador, a fauna that lacks other
taxa of proboscideans (Cisneros, 2005).
Among the three families of proboscideans known from the
Pleistocene of North America (Elephantidae, Gomphotheriidae,
Mammutidae), only the Gomphotheriidae occurs in South America.
There have been numerous studies of the taxonomy, biogeography,
and paleoecology of South American gomphotheres over the past
decade (e.g., S
anchez-Chill
on et al., 2004; Prado et al., 2005;
Ferretti, 2008; Moth
e et al., 2012, 2013; Lucas, 2013; Moth
e and
Avilla, 2015). The taxonomy of Pleistocene gomphotheres in
South America is complicated because as many as four genera have
been recognized, including Cuvieronius. Several recent taxonomic
reviews of South American Pleistocene gomphotheres have
reduced the number of valid species to two (Moth
e et al., 2012,
2013; Lucas, 2013), Cuvieronius hyodon and Notiomastodon pla-
tensis. Notiomastodon can be separated from Cuvieronius by “...the
absence of spiraled torsion and spiral enamel band in upper tusks
… andmolar teethmore complex andwith larger number of cones”
(Moth
e et al., 2012, p. 6). South American gomphotheres previously
referred to the genera Haplomastodon and Stegomastodon are
included under Notiomastodon, following Moth
e et al. (2012, 2013)
and Lucas (2013). Haplomastodon is a synonym of Notiomastodon,
whereas Stegomastodon is restricted to Blancan and early Irving-
tonian faunas from North America (Morgan and Lucas, 2011; Lucas,
2013; Moth
e and Avilla, 2015).
With the exception of a few records from Ecuador and Peru, the
Pleistocene distribution of Cuvieronius and Notiomastodon in South
America is non-overlapping. Cuvieronius is mostly restricted to
upland sites in the Andes of western South America, including
Ecuador, Peru, and Bolivia, although this genus is known from a few
lowland localities in Ecuador (Moth
e and Avilla, 2015). The adap-
tation of Cuvieronius to the South American uplands is supported
not only by its geographic distribution, but also by isotopic studies
(Sanchez-Chill
on et al., 2004; Moth
e et al., 2013). Notiomastodon is
found primarily in lowland sites, but does occur in several Andean
localities in Colombia, Ecuador, and Peru (Moth
e and Avilla, 2015).
Notiomastodon is widely distributed throughout much of South
America where Cuvieronius has not been found, including Chile,
Argentina, Uruguay, Paraguay, Brazil, Colombia, and Venezuela.
Notiomastodon is not known from Surinam and the Guyanas, and
there are very few records from the northern Amazon basin (Moth
e
and Avilla, 2015).
The paleoecology of Cuvieronius in North America and South
America appears to be somewhat contradictory. Cuvieronius in
South America is primarily restricted to the highlands in the An-
dean region, with a few lowland records from Ecuador and Peru
(Moth
e and Avilla, 2015). In contrast, Cuvieronius in Central
America is found primarily in lowland sites, including the speci-
mens from the Pearl Islands that were collected on the continental
shelf below modern sea level. Late Pleistocene proboscideans from
similar lowland tropical faunas in northern South America are
mostly Notiomastodon, including several localities in northwestern
ternational xxx (2015) 1e14 11Colombia less than 400 km southeast of the Pearl Islands (Moth
e
mphotheres (Mammalia: Proboscidea: Gomphotheriidae) from the
, http://dx.doi.org/10.1016/j.quaint.2015.11.003
ry Inet al., 2013; Moth
e and Avilla, 2015). The closest site in South
America where Cuvieronius has been identified is in northern
Ecuador, about 1000 km south of the Pearl Islands (Moth
e and
Avilla, 2015). There do not appear to be any obvious geographic
barriers between Panama and Colombia in the late Pleistocene that
would have limited the dispersal of Cuvieronius south from Central
America into northern South America or Notiomastodon north from
Colombia and Venezuela into Panama. During low sea level stands
of the Pleistocene, narrow coastal corridors would appear to have
functioned as natural dispersal routes along the Pacific coast be-
tween Panama and Colombia and the Caribbean coast between
Panama and Colombia and Venezuela.
The apparent discrepancy between the biogeography and
paleoecology of Cuvieronius in North America compared South
America may result from the difficulty in identifying isolated teeth
of gomphotheres. A gomphothere m3 from the Pearl Islands is
similar to the North American Pliocene and early Pleistocene
(Blancan and early Irvingtonian) genus Stegomastodon, based on
the presence of 5½ lophs/lophids, incipient double trefoiling, and
numerous accessory cusps. The early Blancan species S. primitivus
has similar dental characters to the Pearl Islands gomphothere m3,
whereas the late Blancan and early Irvingtonian species S. mirificus
has 6½ or more lophs/lophids on the M3/m3, double trefoiling, and
highly complicated enamel (Morgan and Lucas, 2011). Despite the
general dental similarities, it is unlikely that the Pearl Islands m3
represents Stegomastodon because there is no evidence of Blancan
and early Irvingtonian vertebrate faunas in Panama. Moreover, the
Pliocene and early Pleistocene was a period of generally high
worldwide sea levels, whereas the teeth from the Pearl Islands
must date to a glacial interval based on their occurrence on the
continental shelf below modern sea level.
Prior to recent taxonomic revisions (Moth
e et al., 2012; Lucas,
2013), South American gomphotheres now referred to Notiomas-
todon platensis were often placed in the genus Stegomastodon. This
identification was based on the overall similarity between Notio-
mastodon (including Haplomastodon) and Stegomastodon, including
complicated teeth, absence of lower tusks, and gently curved to
nearly straight upper tusks lacking torsion and an enamel band.
Most proboscidean workers now consider Stegomastodon to be a
strictly North American genus, and regard its similarity to Notio-
mastodon as an example of morphological convergence (Moth
e
et al., 2012; Lucas, 2013). However, the general similarity of
Notiomastodon to Stegomastodon, and the superficial resemblance
of at least one of the gomphothere teeth from the Pearl Islands to
Stegomastodon, leads to the suggestion that both Cuvieronius and
Notiomastodon might be present in the sample of gomphothere
teeth from the Pearl Islands.
Detailed comparisons of gomphothere specimens from Central
America with Notiomastodon from northern South America and
Cuvieronius from southern South America, as well as the discovery
of more diagnostic specimens in Central America, preferably
including jaws and skulls, will be required before the identification
of tropical American gomphotheres can be fully resolved. For pur-
poses of the present study, we follow current taxonomic doctrine
and recognize the gomphothere teeth from the Pearl Islands as
Cuvieronius hyodon, with the caveat that further study may require
a name change for at least one of the specimens.
5.4. Proboscidean fossils from the continental shelf
The discovery of four gomphothere teeth from the continental
shelf in the Gulf of Panama has prompted a more comprehensive
review of Quaternary fossils of large terrestrial mammals from the
continental shelf. Quaternary proboscidean teeth are well known
G.S. Morgan et al. / Quaterna12from the continental shelf off the Atlantic Coast of the northeastern
Please cite this article in press as: Morgan, G.S., et al., Quaternary go
continental shelf, Pearl Islands, Panama, Quaternary International (2015)United States (Whitmore et al., 1967) and in the North Sea (van
Kolfschoten and Laban, 1995; Mol et al., 2006), but are not well
documented from tropical regions.Whitmore et al. (1967) recorded
teeth of mammoths (Mammuthus) or mastodons (Mammut) from
more than 40 sites at depths of 20e120 m along the continental
shelf of the western North Atlantic Ocean, from the latitude of
Massachusetts south to North Carolina. Large numbers of Pleisto-
cene fossils representing a wide variety of terrestrial mammals
have been dredged by fisherman from the Southern Bight of the
North Sea between England and the Netherlands (van Kolfschoten
and Laban,1995; Mol et al., 2006). Among the most abundant of the
North Sea Pleistocene fossils are isolated teeth of the woolly
mammoth Mammuthus primigenius. Other reports of proboscidean
teeth from the continental shelf include records from Japan,
southern California, and Brazil (Whitmore et al., 1967; Lopes and
Buchmann, 2011).
Several factors help to explain the abundance of proboscidean
teeth in fossil samples dredged from the continental shelf by fish-
erman. Proboscidean teeth are large and sturdy, so would be more
likely to have survived on the sea floor for more than 10,000 years.
Teeth of the American mastodon (Mammut americanum) are more
common on the northeastern U. S. continental shelf than are
mammoth teeth (Mammuthus columbi and M. primigenius), at least
in part because mastodon teeth are stronger, being composed of a
continuous layer of thick enamel. Mammoth teeth consist of plates
of dentine surrounded by rather thin enamel and held together by
softer cement, causing the teeth to break apart between the plates
(Whitmore et al., 1967). The teeth of Cuvieronius are similar to teeth
of Mammut, with a continuous layer of thick enamel. Whitmore
et al. (1967) mentioned only a few other species of large Pleisto-
cene mammals caught in nets by fisherman off the northeastern
coast of the United States, including the woodland musk ox Boot-
herium and the large cervid Cervalces. A diverse sample of large
Pleistocene mammals, the so-called “Mammoth Fauna,” is known
from the shallow waters of the North Sea, including woolly
mammoth, woolly rhino, horse, Irish elk, muskox, bison, cave bear,
and cave lion, among others (van Kolfschoten and Laban, 1995; Mol
et al., 2006).
There are several examples of Quaternary vertebrate fossils
found on the continental shelf in subtropical regions closer to
Panama. Fossils of Mammut americanum, giant ground sloth Ere-
motherium laurillardi, Bison, and giant land tortoise Hesperotestudo
crassiscutata have been caught in shrimp nets at depths of about
10 m in Nassau Sound, a small embayment of the Atlantic Ocean at
the mouth of the Nassau River in northeastern Florida at about 30
North latitude (FLMNH vertebrate paleontology collection). Almost
all of these fossils have attached specimens of modern marine in-
vertebrates. Fossils of the pampathere Holmesina, the cheetah-like
cat Miracinonyx, the horse Equus, and a proboscidean were
collected by a scuba diver from a depth of about 20 m in the Gulf of
Mexico about 25 km west of St. Petersburg, Florida at about 28
North latitude (Morgan and Seymour, 1997; FLMNH vertebrate
paleontology collection). Several of these specimens also had
attached marine invertebrates, including coral. Tunnell (1991) re-
ported a mammoth tooth collected by a commercial shrimp trawler
from a depth of 55 m on the continental shelf off Port Isabel along
the Gulf Coast of Texas at about 26 North latitude.
Fossils of large Pleistocene mammals have been caught by
fisherman in bottom trawlers from depths between 20 and 50 m on
the Atlantic continental shelf about 20e40 km offshore from the
State of Rio Grande do Sul in southern Brazil, between 31 and 33
South latitude (Lopes and Buchmann, 2011). The Brazilian fossils
include the tooth of a gomphothere and a partial skull, humerus,
and femur of the toxodont Toxodon, all of which had attached
ternational xxx (2015) 1e14specimens of modern marine invertebrates. The gomphothere
mphotheres (Mammalia: Proboscidea: Gomphotheriidae) from the
, http://dx.doi.org/10.1016/j.quaint.2015.11.003
Zamora, A.L., 2007. The proboscideans (Mammalia) from Mesoamerica. Qua-
ternary International 169e170, 17e23.
Cope, E.D., 1893. A Preliminary Report on the Vertebrate Paleontology of the Llano
th
ry Intooth, a lower m3 of Notiomastodon platensis (referred to Steg-
omastodon waringi by Lopes and Buchmann, 2011, but see taxo-
nomic discussion above), is of particular interest because of its
similarity to the occurrence of the gomphothere teeth from the
Pearl Islands. This tooth has 5½ lophids that are angled from
anterior to posterior and complicated enamel (Lopes and
Buchmann, 2011), and bears a strong resemblance to a lower m3
(STRI/CTPA 1) from the Pearl Islands here referred to Cuvieronius
hyodon. We are not aware of any published records of terrestrial
vertebrate fossils from the continental shelf along the Pacific Coast
between southern California and the Pearl Islands or in the Gulf of
Mexico or the Caribbean Sea south of Florida and Texas.
6. Conclusions
Four proboscidean teeth from the continental shelf near the
Pearl Islands in the Gulf of Panama, about 50e80 km offshore from
the southern coast of Panama, are identified as the Pleistocene
gomphothere Cuvieronius hyodon. Three complete third molars
from the Pearl Islands, two M3s and one m3, exhibit a range of
dental morphology: from 4½ to 5½ lophs/lophids that are either
horizontal or set at an angle to the long axis of the tooth and rather
simple enamel with single trefoils and limited development of
small accessory cusps to more complex enamel with incipient
double trefoils and numerous accessory cusps. Despite a rather
significant range of dental variation, teeth of Cuvieronius from the
southern United States, Mexico, and Central America, as well as the
Pearl Islands, are referred to the pan-American species C. hyodon,
which is also known from the Andean region of South America.
Cuvieronius can be differentiated from the closely related by
Rhynchotherium by the shortened mandibular symphysis, lack of
lower tusks, and more complicated enamel on the cheek teeth,
particularly the M3s/m3s. Cuvieronius and Rhynchotherium are
closely related based on the shared-derived character of spiraled
upper tusks. The biochronology of these two genera in North
America suggests an ancestoredescendant relationship: Rhyncho-
therium is known only from late Hemphillian and Blancan faunas;
Cuvieronius is restricted to Irvingtonian and Rancholabrean faunas.
The absence of Cuvieronius in temperate North American late
Blancan faunas suggests this genus may have evolved from Rhyn-
chotherium in Central America. Cuvieronius reached South America
in the early Pleistocene where it is first recorded from the Tarija
fauna in Bolivia. Cuvieronius is the only Pleistocene gomphothere in
Central America. In South America, this genus is primarily
restricted to highland sites in Ecuador, Peru, and Bolivia. Notio-
mastodon is the common gomphothere in lowland Pleistocene
faunas in South America, including sites in Colombia and Venezuela
that are within 400 km of the Pearl Islands. Similarities between
teeth of Notiomastodon and at least one of the gomphothere teeth
from the Pearl Islands, and the lack of geographic barriers between
Panama and northern South America during the late Pleistocene,
suggest that the taxonomy of lowland gomphotheres in the
northern Neotropics needs further study.
Two teeth of Cuvieronius hyodon from the Pearl Islands were
recovered in nets by shrimp fisherman from depths of about 90 m,
indicating that these fossils date to the Last Glacial Maximum be-
tween 30 and 15 ka, when sea level was as much as 120 m lower
than present and the Gulf of Panama was dry land. Large areas of
the continental shelf worldwide were subaerially exposed for sig-
nificant periods of time since continental glaciation commenced at
the beginning of the Pleistocene about 2.6 Ma, and should provide
an excellent source of Pleistocene fossils of proboscideans and
other large land mammals. Nonetheless, Pleistocene fossils from
the continental shelf are only rarely reported, and are particularly
G.S. Morgan et al. / Quaternauncommon from tropical regions such as Panama. Only in the North
Please cite this article in press as: Morgan, G.S., et al., Quaternary go
continental shelf, Pearl Islands, Panama, Quaternary International (2015)Estacado. Texas Geological Survey, 4 Annual Report, 136 p.
Ferretti, M.P., 2008. A review of South American proboscideans. New Mexico
Museum of Natural History and Science Bulletin 44, 381e391.
Fischer de Waldheim, G., 1814. Zoognosia, Tabulis Synopticis Illustrat, vol. 3, 694 p.
Gazin, C.L., 1957. Exploration for the Remains of Giant Ground Sloths in Panama.
Smithsonian Institution Annual Report 1956, pp. 341e354.
Gibbard, P.L., Head, M.J., Walker, M.J.C., the Subcommission on Quaternary Stra-
tigraphy, 2010. Formal ratification of the Quaternary system/period and the
Pleistocene series/epoch with a base at 2.58 Ma. Journal of Quaternary Science
25, 96e102.
Hay, O.P., 1926. A collection of Pleistocene vertebrates from southwestern Texas.
Proceedings of the United States National Museum 68 (24), 1e18.
Hibbard, C.W., Dalquest, W.W., 1966. Fossils from the Seymour Formation of Knox
and Baylor counties, Texas, and their bearing on the late Kansan climate of that
region. Contributions from the Museum of Paleontology, University of Michigan
21 (1), 1e66.
Kolfschoten, T. van, Laban, C., 1995. Pleistocene terrestrial mammal faunas from the
North Sea. Mededelingen Rijks Geologische Dienst 52, 135e151.Baskin, J.A., Thomas, R.G., 2007. South Texas and the Great American Interchange.
Gulf Coast Association of Geological Societies Transactions 57, 37e45.
Bell, C.J., Lundelius Jr., E.L., Barnosky, A.D., Graham, R.W., Lindsay, E.H., Ruez Jr., D.R.,
Semken Jr., H.A., Webb, S.D., Zakrzewski, R.J., 2004. The Blancan, Irvingtonian,
and Rancholabrean mammal ages. In: Woodburne, M.O. (Ed.), Late Cretaceous
and Cenozoic Mammals of North America: Biostratigraphy and Geochronology.
Columbia University Press, New York, pp. 232e314.
Boule, M., Thevenin, A., 1920. Mammiferes fossiles de Tarija, first ed. Imprimerie
nationale, Mission Scientifique, G. de Cr
equi-Monfort et F. S
en
echal de la
Grange, Paris. 256 p.
Cartelle, C., de Iuliis, G., 1995. Eremotherium laurillardi: the Panamerican Late
Pleistocene megatheriid sloth. Journal of Vertebrate Paleontology 15, 830e841.
Cione, A.L., Tonni, E.P., 1995. Chronostratigraphy and “Land Mammal Ages” in the
Cenozoic of southern South America: principles, practices, and the “Uquian”
problem. Journal of Paleontology 69, 135e159.
Cisneros, J.C., 2005. New Pleistocene vertebrate fauna from El Salvador. Revista
Brasileira de Paleontologia 8, 239e255.
Cope, E.D., 1884. The extinct Mammalia of the Valley of Mexico. Proceedings of the
American Philosophical Society 22 (117), 1e21.Sea between the Netherlands and England (van Kolfschoten and
Laban, 1995; Mol et al., 2006), and to a lesser extent the western
North Atlantic off the northeastern coast of the United States
(Whitmore et al., 1967), has there been a systematic attempt to
document the Pleistocene mammal fauna recovered from the
continental shelf. Elsewhere, information on late Pleistocene
vertebrate fossils from the continental shelf has been obtained
primarily from fishermen who occasionally notify paleontologists
at museums or universities about fossils recovered from their nets.
Interviewing fisherman in Panama who net shrimp or fish in the
shallow waters of the Gulf of Panama would probably reveal the
existence of more Quaternary fossils than the four gomphothere
teeth reported here.
Acknowledgments
David Bohaska assisted in our research on specimens in the U. S.
National Museum of Natural History (USNM) from El Hatillo, Pan-
ama collected by Lewis Gazin. Dimila Moth
e from the Laborat
orio
de Mastozoologia (UNIRIO) in Rio de Janeiro, Brazil and Marco
Ferretti, University of Firenze, Italy, provided helpful information
on South American gomphotheres. Richard Cooke, Carlos Jaramillo,
George Angehr, and Aaron Wood helped with our studies of a
gomphothere tooth in the collection of STRI/CTPA. This study is part
of the PCP (Panama Canal Project) PIRE (Partnerships in Interna-
tional Research and Education) project and was supported by US
National Science Foundation grant 0966884 (OISE, EAR, DRL) Uni-
versity of Florida Contributions to Paleobiology 815.
References
Arroyo-Cabrales, J., Polaco, O.J., Laurito, C., Johnson, E., Alberdi, M.T., Valerio
ternational xxx (2015) 1e14 13Kurt
en, B., Anderson, E., 1980. The Pleistocene Mammals of North America.
Columbia University Press, New York.
mphotheres (Mammalia: Proboscidea: Gomphotheriidae) from the
, http://dx.doi.org/10.1016/j.quaint.2015.11.003
Lambeck, K., Esat, T.M., Potter, E.K., 2002. Links between climate and sea levels for
the past three million years. Nature 419, 199e206.
Lambert, W.D., 2007. New tetralophodont gomphothere material from Nebraska
and its implications for the status of North American Tetralophodon. Journal of
Vertebrate Paleontology 27, 676e682.
Lambert, W.D., Shoshani, J., 1998. Proboscidea. In: Janis, C.M., Scott, K.M., Jacobs, L.L.
(Eds.), Evolution of Tertiary Mammals of North America, Terrestrial Carnivores,
Ungulates, and Ungulatelike Mammals, vol. 1. Cambridge University Press,
Cambridge, pp. 606e621.
Lopes, R.P., Buchmann, F.S., 2011. Pleistocene mammals from the southern Brazilian
continental shelf. Journal of South American Earth Sciences 31, 17e27.
Lucas, S.G., 2008a. Cuvieronius (Mammalia, Proboscidea) from the Neogene of
Florida. New Mexico Museum of Natural History and Science Bulletin 44,
31e38.
Lucas, S.G., 2008b. Late Cenozoic fossil mammals from the Chapala rift basin, Jalisco,
Mexico. New Mexico Museum of Natural History and Science Bulletin 44,
39e49.
Lucas, S.G., 2013. The palaeobiogeography of South American gomphotheres. Jour-
nal of Palaeogeography 2, 19e40.
Lucas, S.G., 2014. Late Pleistocene mammals from El Hatillo, Panama. Revista Geo-
l
ogica de Am
erica Central 50, 139e151.
Lucas, S.G., Alvarado, G.E., 2010. Fossil Proboscidea from the upper Cenozoic of
Central America: taxonomy, evolutionary and paleobiogeographic significance.
Revista Geol
ogica de Am
erica Central 42, 9e42.
Lucas, S.G., Alvarado, G.E., Vega, E., 1997. The Pleistocene mammals of Costa Rica.
Journal of Vertebrate Paleontology 17, 413e427.
Lucas, S.G., Morgan, G.S., 2008. Taxonomy of Rhynchotherium (Mammalia, Probo-
scidea) from the Miocene-Pliocene of North America. New Mexico Museum of
Natural History and Science Bulletin 44, 71e87.
Lucas, S.G., Morgan, G.S., Estep, J.W., 2000. Biochronological significance of the co-
paleontological, palynological, and archaeological investigations of this part of
the North Sea. Quaternary International 142e143, 178e185.
Morgan, G.S., Hulbert Jr., R.C., 1995. Overview of the geology and vertebrate pale-
ontology of the Leisey Shell Pit Local Fauna, Hillsborough County, Florida.
Bulletin of the Florida Museum of Natural History 37 (Part I), 1e92.
Morgan, G.S., Lucas, S.G., 2003. Mammalian biochronology of Blancan and Irving-
tonian (Pliocene and early Pleistocene) faunas from New Mexico. Bulletin of the
American Museum of Natural History 278, 269e320.
Morgan, G.S., Lucas, S.G., 2011. Stegomastodon (Mammalia: Proboscidea: Gompho-
theriidae) from the Blancan and Irvingtonian (Pliocene and early Pleistocene) of
New Mexico. New Mexico Museum of Natural History and Science Bulletin 53,
570e582.
Morgan, G.S., Seymour, K.L., 1997. Fossil history of the panther (Puma concolor) and
the cheetah-like cat (Miracinonyx inexpectatus) in Florida. Bulletin of the Florida
Museum of Natural History 40, 177e219.
Moth
e, D., Avilla, L.S., 2015. Mythbusting evolutionary issues on South American
Gomphotheriidae (Mammalia: Proboscidea). Quaternary Science Reviews 110,
23e35.
Moth
e, D., Avilla, L.S., Cozzuol, M.A., 2013. The South American gomphotheres
(Mammalia, Proboscidea, Gomphotheriidae): taxonomy, phylogeny, and
biogeography. Journal of Mammalian Evolution 20, 23e32.
Moth
e, D., Avilla, L.S., Cozzuol, M.A., Winck, G.R., 2012. Taxonomic revision of the
Quaternary gomphotheres (Mammalia: Proboscidea: Gomphotheriidae) from
the South American lowlands. Quaternary International 276e277, 2e7.
Osborn, H.F., 1936. Proboscidea. In: Moertheriodea, Deinotheriodea, Mastodontoi-
dea, vol. I. The American Museum Press, New York.
Pearson, G.A., 2005. Late Pleistocene megafaunal deposits on the Isthmus of Panama
and their paleoenvironmental implications. Caribbean Journal of Science 41, 1e13.
Prado, J.L., Alberdi, M.T., Azanza, B., S
anchez, B., Frassinetti, D., 2005. The Pleistocene
gomphotheres (Proboscidea) from South America. Quaternary International
G.S. Morgan et al. / Quaternary International xxx (2015) 1e1414occurrence of the proboscideans Cuvieronius, Stegomastodon, and Mammuthus
in the lower Pleistocene of southern New Mexico. New Mexico Museum of
Natural History and Science Bulletin 16, 209e216.
Lucas, S.G., Morgan, G.S., Estep, J.W., Mack, G.H., Hawley, J.W., 1999. Co-occurrence
of the proboscideans Cuvieronius, Stegomastodon, and Mammuthus in the lower
Pleistocene of southern New Mexico. Journal of Vertebrate Paleontology 19,
595e597.
Lundelius Jr., E.L., 1972. Fossil Vertebrates from the Late Pleistocene Ingleside Fauna,
San Patricio County, Texas. Bureau of Economic Geology, University of Texas at
Austin, Report of Investigations 77, pp. 1e74.
MacFadden, B.J., 2013. Dispersal of Pleistocene Equus (Family Equidae) into South
America and calibration of GABI 3 based on evidence from Tarija, Bolivia. PLoS
ONE 8 (3), e59277. http://dx.doi.org/10.1371/journal.pone.0059277.
MacFadden, B.J., Zeitler, P.K., Anaya, F., Cottle, J.M., 2013. Confirmation of the middle
Pleistocene age of the sedimentary sequence from Tarija, Bolivia. Quaternary
Research 79, 268e273.
Marshall, L., Berta, A., Hoffstetter, R., Pascual, R., Reig, O., Bombin, M., Mones, A.,
1984. Mammals and stratigraphy: geochronology of the continental mammal-
bearing Quaternary of South America. Paleovertebrata, Memoire Extraordi-
naire, pp. 1e76.
Meyer, H. von, 1867. Studien ueber das genus Mastodon. Paleontographica 18, 1e72.
Mol, D., Post, K., Reumer, J.W.F., van der Plicht, J., de Vos, J., van Geel, B., van
Reenen, G., Pals, J.P., Glimmerveen, J., 2006. The Eurogeuldfirst report of thePlease cite this article in press as: Morgan, G.S., et al., Quaternary go
continental shelf, Pearl Islands, Panama, Quaternary International (2015)126e128, 21e30.
S
anchez-Chill
on, B., Prado, J.L., Alberdi, M.T., 2004. Feeding ecology, dispersal, and
extinction of South American Pleistocene gomphotheres (Gomphotheriidae,
Proboscidea). Paleobiology 30, 146e161.
Sanders, A.E., 2002. Additions to the Pleistocene mammal faunas of South Carolina,
North Carolina, and Georgia. Transactions of the American Philosophical Society
92 (5), 1e152.
Savage, D.E., 1955. A survey of various Late Cenozoic vertebrate faunas of the
Panhandle of Texas. Part II. Proboscidea. University of California Publications in
Geological Sciences 31, 51e72.
Tobien, H., 1973. On the evolution of mastodonts (Proboscidea, Mammalia), part 1:
the bunodont trilophodont groups. Notizblatt des Hessischen Landesamtes fur
Bodenforschung zu Wiesbaden 101, 202e276.
Tunnell, J.W., 1991. Pleistocene Vertebrate Fossils from the Continental Shelf, NW
Gulf of Mexico. National Park Service Paleontology Research Abstract Volume,
Technical Report NPS/NRPEFO/NRTR-93/11, p. 57.
Webb, S.D., Dudley, J.P., 1995. Proboscidea from the Leisey Shell Pits, Hillsborough
County, Florida. Bulletin of the Florida Museum of Natural History 37 (Part II),
645e660.
Webb, S.D., Perrigo, S.C., 1984. Late Cenozoic vertebrates from Honduras and El
Salvador. Journal of Vertebrate Paleontology 4, 237e254.
Whitmore Jr., F.C., Emery, K.O., Cooke, H.B.S., Swift, D.J.P., 1967. Elephant teeth from
the Atlantic Continental Shelf. Science 156, 1477e1481.mphotheres (Mammalia: Proboscidea: Gomphotheriidae) from the
, http://dx.doi.org/10.1016/j.quaint.2015.11.003