7 p. : 1 ill. ; 24 cm.Includes bibliographical references (p. 7)

Giovannoli, Leonard.

Goin, Coleman Jett, 1911-

Rabb, George B. (George Bernard), 1930-2017.

Van Voast-American Museum of Natural History Bahama Islands Expedition (1952-1953)

American Museum of Natural History Scientific Publications

M>ie'icnJluseum
PUBLISHED BY THE AMERICAN MUSEUM OF NATURAL HISTORY
CENTRAL PARK WEST AT 79TH STREET, NEW YORK 24, N.Y.
NUMBER 1708 FEBRUARY 19, 1955
Description of a New Subspecies of the
Frog Eleutherodactylus ricordi
from the Bahama Islands
BY COLEMAN J. GoIN
The members of the Van Voast-American Museum of Natural History
Expedition to the Bahama Islands in 1953 collected Eleutherodactylus
from many of the islands from which heretofore very few or no specimens
were known. Mr. George B. Rabb, who is undertaking the study of the
herpetological material collected, has very kindly suggested that I report
on the frogs of this genus. A total of 441 frogs collected by these workers,
plus material already available in museums, makes possible a reevaluation
of this group in the Bahamas. Although I earlier (Goin, 1947, p. 42)
stated the belief that planirostris might be simply a feral waif in the
Bahamas, in the light of this rather extensive recent material I do not
believe that this position is any longer tenable.
The frogs from the islands in the lower portion of Great Bahama Bank,
comprising as they do a rather homogeneous lot, are rather different from
those of the other islands and should be named. I take pleasure in naming
this new form for Prof. J. Speed Rogers, who has constantly encouraged
me in my studies of Eleutherodactylus.
Eleutherodactylus ricordi rogersi, new subspecies
TYPE: A.M.N.H. No. 57564, adult female, collected January 18, 1953,
on Darby Island, Exuma Cays, Bahama Islands, latitude 230 50' S.,
longitude 760 11' W., by George B. Rabb and Leonard Giovannoli.
AMERICAN MUSEUM NOVITATES
PARATYPES: Forty-eight, as follows': Darby Island, Exuma Cays:
U.M.M.Z. No. 110103. Bell Island, Exuma Cays, latitude 240 19' S.,
longitude 760 32' W.: A.M.N.H. Nos. 57565-57569; U.M.M.Z. No.
110102 (5). Cat Island: A.M.N.H. Nos. 57581-57584; M.C.Z. Nos.
21420, 21421; U.M.M.Z. No. 110107 (3). Long Island: A.M.N.H. Nos.
57570-57575; U.M.M.Z. Nos. 110104 (3), 110105 (2). San Salvador
(Watling Island): A.M.N.H. Nos. 57576-57580; C.M. Nos. 20452,
20453; M.C.Z. No. 24585; U.M.M.Z. No. 110106 (5); U.S.N.M. Nos.
66250-66253.
DIAGNOSIS: An Eleutherodactylus allied to planirostris, with the
vomerine teeth in two long, arched series; with the pads of the two outer
fingers larger than those of the inner fingers; and with a pattern of
minute, pale brown specks uniformly distributed on a ground color of
light tan. It differs from ricordi ricordi of Cuba in having the top of the
head much lighter than the dorsum and from planirostris and caspari in
lacking bands on the hind legs and any appreciable amount of chin or
throat pigment. Although no differences between rogersi and planirostris
can be noted in mensural characteristics, the former gives the impression
of being a heavier-bodied frog with a thicker body and legs.
DESCRIPTION OF TYPE: Head slightly broader than distance from
snout to occiput; snout somewhat rounded, upper jaw slightly project-
ing; diameter of eye about equal to distance between eye and nostril;
nostril very near tip of snout; interorbital space greater than diameter
of individual eye; upper eyelids and top of head smooth; dorsum
smooth medially, becoming faintly rugose towards the sides; diameter
of tympanum equal to about half of the diameter of the eye; distance
from eye to tympanum equal to about half of the diameter of the
tympanum. Digital discs present on the tips of all fingers and toes, the
discs of the two outer fingers larger than those of the two inner fingers,
width of disc of second toe about equal to one-third of diameter of
tympanum. Fingers slender, unwebbed, 3-4-2-1 in order of decreasing
length; subarticular tubercles well developed. Toes slender, unwebbed,
4-3-5-2-1 in order of decreasing length. Heels not quite in contact when
legs are flexed with femora held at right angles to body; knees and elbows
in contact when limbs are pressed along sides; heel extending to about
middle of orbit when leg is pressed along body. Venter smooth in center,
A.M.N.H., the American Museum of Natural History.
C.M., Carnegie Museum.
M.C.Z., Museum of Comparative Zoology.
U.M.M.Z., University of Michigan Museum of Zoology.
U.S.N.M., United States National Museum.
2 NO0. 1708
GOIN: NEW FROG
becoming more rugose towards the sides. Under surface of thighs some-
what rugose. Belly disc fairly well developed, with a distinct chest fold
extending between the axillae and a distinct fold across the belly slightly
anterior to the hind limbs. Tongue oval, not notched, free behind; great-
FIG. 1. Dorsal view of the type of Eleutherodactylus ricordi rogersi (A.M.N.H.
No. 57564), showing details of pattern. X 1.5. Drawn by Esther Coogle.
est width of tongue about two-thirds of that of mouth opening. Vomerine
teeth in two long, arched series, extending laterally beyond the level of
the choanae, nearly in contact in the middle.
COLORATION OF TYPE: A narrow, dark band between the eyes sepa-
rating the pale, tannish color of the top of the head from that of the
dorsum. Ground color of dorsum and dorsal surfaces of front and hind
limbs very pale tan, more or less uniformly covered with minute, uni-
formly distributed flecks of darker brown. Above the axillae and just
anterior to the sacral hump these flecks tend to become confluent, thus
forming two indistinct, short, narrow, dark bars across the back. Flecks
uniformly distributed over upper surface of hind legs. Margin of lower
lip uniform, chin and throat immaculate to naked eye, although scattered,
minute pigment cells can be seen under magnification. Belly immaculate.
MEASUREMENTS OF TYPE (IN MILLIMETERS): Snout-to-vent length,
31.8; head width, 12.3; tip of snout to posterior margin of tympanum,
11.2; diameter of eye, 3.5; diameter of tympanum, 2.0; hind leg (vent to
tip of longest toe), 40.8; hind leg (vent to heel), 24.2.
1955 3
AMERICAN MUSEUM NOVITATES
VARIATION: In rogersi, as in the other races of ricordi, individuals
with dorsolateral stripes occur. Of the 48 paratypes, dorsolateral stripes
are found on two from Long Island and three from Bell Island, Exuma
Cays. In these individuals the dorsolateral stripes seem to be simply
pigmentless areas, and the stripes are not pronouncedly bordered with
dark as they are in some species of Eleutherodactylus.
There seems to be some ontogenetic change in coloration; some im-
mature individuals have very indistinct bars on the hind legs. In none of
the paratypes that are subadult or larger, however, have these bars per-
sisted; all these have the dorsal surface of the thighs speckled rather than
barred. The same is true of the dorsal pigment. In tiny individuals it
seems to be more concentrated in larger blotches, so that they resemble
mottled planirostris. In larger specimens the pigment is so distributed as
to give a definite speckled pattern. Although even in the large individ-
uals there is some confluence of pigment above the shoulders, all speci-
mens of the population nonetheless are pale, speckled frogs that do not
show the darker mottled condition obtained in planirostris.
All in all, the population in the southern and eastern portions of the
Great Bahama Bank seems to be rather a homogeneous group of pale,
speckled frogs.
The populations occupying Andros and Eleuthera Islands and Bimini,
while included in the range of rogersi, are intentionally omitted from the
list of paratypes. While these populations seem referable to rogersi, some
individuals from them approach planirostris more closely. I believe this
is due to a gene flow, probably from near-by New Providence in the case
of Andros and Eleuthera and perhaps from Florida in the case of Bimini.
EVOLUTION OF SPECIES IN BAHAMA ISLANDS: It is now apparent that
E. ricordi, in one form or another, is widely distributed in the Bahamas
south and east to the Crooked Island Passage.
Specimens from the lower portion of the Great Bahama Bank (rogersi)
are pale tannish or yellowish frogs, speckled with pale brown. I believe
that evolution has also been taking place in the population of the Little
Bahama Bank, although I do not feel the need to recognize the form
taxonomically at the present time. Specimens from Grand Bahama Is-
land and Great Abaco are dark gray in ground color, with rather large,
discrete, dark spots scattered over the backs. One thing that impels me
to refrain from naming this population now is the fact that the bulk of
the fresh material I have examined from this bank is from a single local-
ity, Marsh Harbour, Great Abaco. I do not believe this form should be
named until it is demonstrated by adequate fresh material from several
4 NO0. 1708
GOIN: NEW FROG
localities that the Marsh Harbour specimens do not represent a restricted,
local population. In between these two populations of Great Bahama
Bank and Little Bahama Bank we have the type locality of planirostris
(New Providence), which is occupied by a frog population essentially
indistinguishable from the widespread populations of Cuba and Florida
and like the frogs of neither the northern nor the southern Bahamas.
Thus we have a rather curious situation, with the population of a com-
paratively small island in the middle of the Bahamas being like the Cuba
and Florida populations while on the islands both to the north and south
of this, speciation or incipient speciation has occurred.
I believe that this rather queer circumstance can be readily explained
by a combination of geologic and historic events.
It would seem to me that at some time in the geologic past, planirostris
(or its progenitor) reached the Bahamas from Cuba and evolved at two
centers, the Little Bahama group and the Great Bahama group. The
thesis presented so vividly by Barbour and Shreve (1935) that such events
might have occurred during Pleistocene times when the Bahamas were
a few large land masses rather than archipelagos of small islands would
certainly be consistent with this idea. With the elevation of sea level,
these frogs would then be broken up into small island populations that
were more or less isolated.
To my mind, E. r. planirostris is a frog that lends itself to human
transportation, as witness its relatively recent spread and its present wide
distribution in Florida and Jamaica.
There seems to be no doubt that New Providence has been the chief
port of entry to the Bahamas since the first English settlement at Nassau
was founded about 1630. It is also known that much of the early travel
was from Cuba to Nassau, as it was from Havana that several of the
earlier Spanish raiding expeditions set sail. At intervals during the next
century the Spaniards were from time to time in control of Nassau, at
one time for as much as 20 consecutive years (Wright, 1905, p. 422).
If man entered the picture and introduced planirostris to New Provi-
dence from Cuba, planirostris might swamp the New Providence popu-
lation while the frogs on the other islands were rather free from gene
flow. As this introduction to New Providence may have occurred more
than once, or is perhaps even a continuing process, it would be readily
understandable that the frogs from this small island in the middle of the
Bahamas are like those from Cuba and Florida, while the frogs on the
other, more isolated, islands have been relatively free from gene flow and
have remained differentiated.
1955 5
AMERICAN MUSEUM NOVITATES
The populations of Eleuthera and Andros probably have been polluted
in part from neighboring New Providence; hence it would be natural for
them to exhibit planirostris influence.
The population of Bimini likewise shows some indication of gene flow.
Although Shreve (1945, p. 117) recently pointed out that ricordi,
planirostris, and caspari really represent a group of closely allied forms,
no direct comparison of them has been published. I therefore take this
opportunity to present a key to the subspecies of ricordi.
KEY TO THE SUBSPECIES OF Eleutherodactylus ricordi
1. Top of head with pale triangular area which is definitely lighter than the
dorsum........................... . 2
Top of head without a triangular area definitely lighter than the dorsum;
top of head and dorsum vermiculated or marbled with chocolate brown
(the highlands of Oriente, Cuba) . . . . . . . . . . . . E. r. ricordi
2. Edge of lower lip mottled; chin and throat with faint to pronounced pigment
flecks; pigment on upper surface of thighs often arranged in definite cross
bands in adults . . . . . . . . . . . . . . .
.
. . . . . . 3
Edge of lower lip pale; chin and throat essentially immaculate; dorsum and
upper surface of thighs with numerous, more or less uniformly scattered,
minute, pale brown specks (islands of the Great Bahama Bank except
New Providence) . . . . . . . . . . . . . . . . . . . . E. r. rogersi
3. One or two pairs of distinct, chocolate brown, dark spots just above and
anterior to the groin (the Trinidad Mountains in Las Villas, Cuba)
. ......................
.
E. r. caspari
No pronounced, distinct, chocolate brown spots just above the groin (New
Providence, Cuba, Isle of Pines, peninsular Florida, parts of Jamaica,
Grand Cayman, Cayman Brac, and provisionally Grand Bahama and
Great Abaco .E.................E. r. planirostris
MATERIAL: In addition to material previously recorded in the litera-
ture and the type and paratypes listed above, I have recently examined
the following specimens from the Bahama Islands. The specimens with
the Van Voast-American Museum of Natural History field numbers are
to be divided between the American Museum of Natural History and the
University of Michigan Museum of Zoology. Eleuthera, New Portsmouth
(Rock Sound): Van Voast-A.M.N.H. Nos. 2431-2451, 2517, 2518. New
Providence, near Nassau: Van Voast-A.M.N.H. No. 2686; Bay Street,
Nassau: Van Voast-A.M.N.H. Nos. 2708-2736. Andros, south shore,
entrance, Fresh Creek: Van Voast-A.M.N.H. Nos. 2871-2873, 2889-
2893. Grand Bahama, west end: Van Voast-A.M.N.H. Nos. 3427-3430.
Great Abaco, Marsh Harbour: Van Voast-A.M.N.H. Nos. 3501-3806.
South Bimini, east end: C.M. Nos. 32560-32562; near Nixon's Har-
bour: C.M. Nos. 32611, 32612.
ACKNOWLEDGEMENTS: I am indebted to Messrs. George B. Rabb and
6 NO0. 1708
GOIN: NEW FROG
Charles M. Bogert for the privilege of studying the specimens collected
by the Van Voast-American Museum of Natural History Expedition to
the Bahamas. Dr. Doris M. Cochran of the United States National
Museum, Mr. Arthur Loveridge of the Museum of Comparative Zoology,
and Dr. M. Graham Netting and Mr. Neil D. Richmond of Carnegie
Museum have, as usual, courteously and speedily made comparative ma-
terial in their care available to me. The drawing of the type is from the
facile pen of Miss Esther Coogle. To all of these I owe my thanks.
LITERATURE CITED
BARBOUR, THOMAS, AND BENJAMIN SHREVE
1935. Concerning some Bahamian reptiles, with notes on the fauna. Proc.
Boston Soc. Nat. Hist., vol. 40, no. 5, pp. 347-366.
GoIN, COLEMAN JETT
1947. Studies on the life history of Eleutherodactylus ricordii planirostris
(Cope) in Florida. Univ. Florida Studies, biol. sci. ser., vol. 4, no. 2,
xi + 66 pp., 7 text figs., 6 pls.
SHREVE, BENJAMIN
1945. Application of the name Eleutherodactylus ricordii. Copeia, 1945,
no. 2, p. 117.
WRIGHT, JAMES M.
1905. History of the Bahama Islands, with a special study of the abolition
of slavery in the colony. In Shattuck, George B., The Bahama
Islands. New York, the Macmillan Co., pp. 419-583.
1955 7



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