Frugivory and Seed Dispersal by Hyla truncata, a Neotropical Treefrog

Abstract

We report observations on the use of fruits by a medium sized (ca. 39 mm SVL) neotropical hylid treefrog Hyla truncata, which is usually found in axils of the terrestrial bromeliad, Neoregelia cruenta (Bromeliaceae)
during the day.

Full text

Frugivory and Seed Dispersal by Hyla truncata, a Neotropical Treefrog
Author(s): Helio R. da Silva, Mônica C. de Britto-Pereira, Ulisses Caramaschi
Source:
Copeia,
Vol. 1989, No. 3 (Aug. 8, 1989), pp. 781-783
Published by: American Society of Ichthyologists and Herpetologists
Stable URL: http://www.jstor.org/stable/1445517
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HERPETOLOGICAL NOTES
HERPETOLOGICAL NOTES
76SR00819 with the University of Georgia
(SREL).
LITERATURE CITED
FERGUSON,
D. E. 1971. The sensory basis of orien-
tation in amphibians.
Ann. N.Y. Acad. Sci. 188:30-
36.
GORDON,
R. E. 1961. The movement of displaced
green salamanders.
Ecology 42:200-202.
GRANT,
D., O. ANDERSON
AND V. C. TWITTY. 1968.
Homing orientation by olfaction in newts (Taricha
rivularis).
Science 160:1354-1355.
HERSHEY,
J. L., AND D. C. FORESTER.
1980. Sensory
orientation in Notophthalmus
v. viridescens
(Am-
phibia:
Salamandridae).
Can.
J. Zool. 58:266-276.
HOLOMUZKI, J. R. 1982. Homing behavior of Des-
mognathus
ochrophaeus along a stream.
J. Herpetol.
16:307-309.
JAEGER,
R. G., AND W. F. GERGITS. 1979. Intra- and
interspecific
communication
in salamanders
through
chemical
signals
on the substrate.
Anim. Behav.
27:
150-156.
LANDRETH,
H. F., AND D. E. FERGUSON.
1967. Newt
orientation by sun-compass.
Nature 215:516-518.
MADISON,
D. M. 1969. Homing behavior
of the red-
cheeked salamander,
Plethodon
jordani. Anim. Be-
hav. 17:25-39.
MCGAVIN,
M. 1978. Recognition ofconspecific
odors
by the salamander Plethodon
cinereus.
Copeia 1978:
356-358.
PHILLIPS,
J. B. 1986. Magnetic compass
orientation
in the eastern red-spotted
newt (Notophthalmus
vir-
idescens).
J. Comp. Physiol. (A) 158:103-109.
SHOOP,
C. R. 1965. Orientation of Ambystoma
mac-
ulatum: movements to and from breeding ponds.
Science 149:558-559.
. 1968. Migratory orientation of Ambystoma
maculatum. Movements near breeding ponds and
displacements
of migrating individuals.
Biol. Bull.
135:230-238.
, AND
T. L. DOTY.
1972. Migratory
orienta-
tion by marbled salamanders
(Ambystoma opacum)
near a breeding area. Behav. Biol. 7:131-136.
TRISTRAM,
D. A. 1977. Intraspecific olfactory com-
munication
in the terrestrial
salamander,
Plethodon
cinereus.
Copeia 1977:597-600.
TWITTY,
V. C. 1966. Of scientists and salamanders.
W. H. Freeman & Co., San Francisco,
California.
WHITFORD,
W. G., AND A. VINEGAR. 1966. Homing,
speed of migration, over wintering of larvae, and
sex ratio in breeding populations
of Ambystoma
mac-
ulatum.
Copeia 1966:515-519.
JOANNE H. MCGREGOR, Savannah River Ecology
Laboratory, Drawer E, Aiken, South Carolina
29801 and WILLIAM R. TESKA, Department of
Biology, Furman University, Greenville, South
Carolina 29613. Accepted 9 Nov. 1988.
76SR00819 with the University of Georgia
(SREL).
LITERATURE CITED
FERGUSON,
D. E. 1971. The sensory basis of orien-
tation in amphibians.
Ann. N.Y. Acad. Sci. 188:30-
36.
GORDON,
R. E. 1961. The movement of displaced
green salamanders.
Ecology 42:200-202.
GRANT,
D., O. ANDERSON
AND V. C. TWITTY. 1968.
Homing orientation by olfaction in newts (Taricha
rivularis).
Science 160:1354-1355.
HERSHEY,
J. L., AND D. C. FORESTER.
1980. Sensory
orientation in Notophthalmus
v. viridescens
(Am-
phibia:
Salamandridae).
Can.
J. Zool. 58:266-276.
HOLOMUZKI, J. R. 1982. Homing behavior of Des-
mognathus
ochrophaeus along a stream.
J. Herpetol.
16:307-309.
JAEGER,
R. G., AND W. F. GERGITS. 1979. Intra- and
interspecific
communication
in salamanders
through
chemical
signals
on the substrate.
Anim. Behav.
27:
150-156.
LANDRETH,
H. F., AND D. E. FERGUSON.
1967. Newt
orientation by sun-compass.
Nature 215:516-518.
MADISON,
D. M. 1969. Homing behavior
of the red-
cheeked salamander,
Plethodon
jordani. Anim. Be-
hav. 17:25-39.
MCGAVIN,
M. 1978. Recognition ofconspecific
odors
by the salamander Plethodon
cinereus.
Copeia 1978:
356-358.
PHILLIPS,
J. B. 1986. Magnetic compass
orientation
in the eastern red-spotted
newt (Notophthalmus
vir-
idescens).
J. Comp. Physiol. (A) 158:103-109.
SHOOP,
C. R. 1965. Orientation of Ambystoma
mac-
ulatum: movements to and from breeding ponds.
Science 149:558-559.
. 1968. Migratory orientation of Ambystoma
maculatum. Movements near breeding ponds and
displacements
of migrating individuals.
Biol. Bull.
135:230-238.
, AND
T. L. DOTY.
1972. Migratory
orienta-
tion by marbled salamanders
(Ambystoma opacum)
near a breeding area. Behav. Biol. 7:131-136.
TRISTRAM,
D. A. 1977. Intraspecific olfactory com-
munication
in the terrestrial
salamander,
Plethodon
cinereus.
Copeia 1977:597-600.
TWITTY,
V. C. 1966. Of scientists and salamanders.
W. H. Freeman & Co., San Francisco,
California.
WHITFORD,
W. G., AND A. VINEGAR. 1966. Homing,
speed of migration, over wintering of larvae, and
sex ratio in breeding populations
of Ambystoma
mac-
ulatum.
Copeia 1966:515-519.
JOANNE H. MCGREGOR, Savannah River Ecology
Laboratory, Drawer E, Aiken, South Carolina
29801 and WILLIAM R. TESKA, Department of
Biology, Furman University, Greenville, South
Carolina 29613. Accepted 9 Nov. 1988.
Copeia, 1989(3), pp. 781-783
? 1989 by the American Society of
Ichthyologists and Herpetologists
FRUGIVORY AND SEED DISPERSAL BY
HYLA
TRUNCATA,
A NEOTROPICAL TREE-
FROG.-Frogs are known to be carnivorous,
eating mainly arthropods (Duellman and Trueb,
1986). Although consumption of plant material
has been reported in studies on anuran feeding
habits, plants are not regarded as an important
resource in the anuran diet and some authors
suggest the ingestion of plant parts as incidental
(Korschgen and Moyle, 1955; Linzey, 1967;
Hedeen, 1972). Reports on stationary food items
(Alexander, 1964) and non-carnivorous feeding
behavior have been reported for Bufo marinus
(Alexander, 1964; Zug, et al., 1975). B. regularis
(Winston, 1955), and Rana esculenta (Tyler,
1958). Here we report observations on the use
of fruits by a medium sized (ca. 39 mm SVL)
neotropical hylid treefrog Hyla truncata (Fig. 1),
which is usually found in axils of the terrestrial
bromeliad, Neoregelia cruenta (Bromeliaceae)
during the day (Izecksohn, 1971; pers. obs.).
Our field observations were carried out at
Barra de Marica, Rio de Janeiro, Brazil (ca.
22?57'S; 53?08'W), a sand dune ecosystem be-
tween the ocean and a coastal lagoon, typical of
the Brazilian coast. This habitat, called "restin-
ga" (Rizzini, 1979), is composed of shrub tick-
ets, cacti, and terrestrial bromeliads (see Hay et
al., 1981, and Lacerda and Hay, 1982, for a
complete description). The climate of this re-
gion is characterized by a hot rainy summer,
and a dry winter, with the annual temperature
and rainfall varying (on average) between 22 C
and 24 C, and 1000 mm and 1350 mm, respec-
tively (Nimer, 1972).
During the field work performed in the re-
gion since 1986, it was observed that some frogs
transported from the field to the laboratory fre-
quently defecated seeds. To determine if these
observations indicated fruit consumption, 81
adults ofH. truncata were collected between Aug.
1986 and Jan. 1987. The specimens were ob-
tained at sunrise when the frogs were inside
bromeliads, and presumably before much diges-
tion had taken place. As soon as each individual
was collected, it was put inside an icebox to slow
digestion. After each sampling session, the frogs
were killed, the alimentary canal was removed
and its content qualitatively analyzed. Because
our sample size of fruit eating frogs was small,
we have not attempted to determine if there
exist sexual differences in feeding preferences,
Copeia, 1989(3), pp. 781-783
? 1989 by the American Society of
Ichthyologists and Herpetologists
FRUGIVORY AND SEED DISPERSAL BY
HYLA
TRUNCATA,
A NEOTROPICAL TREE-
FROG.-Frogs are known to be carnivorous,
eating mainly arthropods (Duellman and Trueb,
1986). Although consumption of plant material
has been reported in studies on anuran feeding
habits, plants are not regarded as an important
resource in the anuran diet and some authors
suggest the ingestion of plant parts as incidental
(Korschgen and Moyle, 1955; Linzey, 1967;
Hedeen, 1972). Reports on stationary food items
(Alexander, 1964) and non-carnivorous feeding
behavior have been reported for Bufo marinus
(Alexander, 1964; Zug, et al., 1975). B. regularis
(Winston, 1955), and Rana esculenta (Tyler,
1958). Here we report observations on the use
of fruits by a medium sized (ca. 39 mm SVL)
neotropical hylid treefrog Hyla truncata (Fig. 1),
which is usually found in axils of the terrestrial
bromeliad, Neoregelia cruenta (Bromeliaceae)
during the day (Izecksohn, 1971; pers. obs.).
Our field observations were carried out at
Barra de Marica, Rio de Janeiro, Brazil (ca.
22?57'S; 53?08'W), a sand dune ecosystem be-
tween the ocean and a coastal lagoon, typical of
the Brazilian coast. This habitat, called "restin-
ga" (Rizzini, 1979), is composed of shrub tick-
ets, cacti, and terrestrial bromeliads (see Hay et
al., 1981, and Lacerda and Hay, 1982, for a
complete description). The climate of this re-
gion is characterized by a hot rainy summer,
and a dry winter, with the annual temperature
and rainfall varying (on average) between 22 C
and 24 C, and 1000 mm and 1350 mm, respec-
tively (Nimer, 1972).
During the field work performed in the re-
gion since 1986, it was observed that some frogs
transported from the field to the laboratory fre-
quently defecated seeds. To determine if these
observations indicated fruit consumption, 81
adults ofH. truncata were collected between Aug.
1986 and Jan. 1987. The specimens were ob-
tained at sunrise when the frogs were inside
bromeliads, and presumably before much diges-
tion had taken place. As soon as each individual
was collected, it was put inside an icebox to slow
digestion. After each sampling session, the frogs
were killed, the alimentary canal was removed
and its content qualitatively analyzed. Because
our sample size of fruit eating frogs was small,
we have not attempted to determine if there
exist sexual differences in feeding preferences,
781 781

COPEIA, 1989, NO. 3
and we delimit content analysis only by recovery
location, stomach vs. intestinal.
Ants, grasshoppers, beetles, spiders, cock-
roaches, dragonfly naiads, beetle and butterfly
larvae, fruits and seeds were found. Insects and
spiders were listed together as arthropods. Of
the 81 stomachs analyzed, 53% were empty, 27%
had only arthropods, 14% had only fruits, and
6% had fruits as well as arthropods. Excluding
the empty stomachs, 58% of the remainder con-
tained only arthropods, 29% only fruits, and
13% fruits and arthropods. Of the 81 intestines
analyzed, 40% were empty, 53% had arthro-
pods, and 7% had only seeds. Excluding the
empty ones, 88% contained arthropods, and
12% had only seeds. The presence of fruits was
recorded in both male and female treefrogs.
The fruits and seeds obtained were small,
ranging from 3-10 mm in length, and pertained
to Anthurium harrisii (Araceae), Erythroxylum
ovalifolium
(Erythroxylaceae), and two other un-
identified plant species. The first two plants were
present in 4.9% and 6.2%, respectively, of all
stomachs analyzed, and 10.5% and 13.3% ex-
cluding the empty ones. In the intestines, only
seeds of A. harrisii were found. We think that
seeds of E. ovalifolium
were not registered in the
intestines because they were defecated or they
had not reached the intestine. We do not believe
it is possible for the frogs to digest this seed
because of its thick shell. The other two plant
species were found in only one stomach each.
The fruits were swallowed whole. Seeds in
the recta were always without pulp, but pulp
was present all through the small intestine.
Therefore, it seems that the fruits were being
digested and may be regarded as part of the
frog's diet.
In order to test the hypothesis that the fruits
were intentionally ingested by the frogs, labo-
ratory experiments and field observations were
made. In the laboratory, 146 fruits of A. harrisii
were offered to 10 H. truncata kept in different
terraria during a week. Fruits of E. ovalifolium
were not offered to the animals in captivity be-
cause they decay very rapidly. In the field, ob-
servations were made at night to watch the feed-
ing activity of the frogs.
Forty-seven percent of the fruits of A. harrisii
were eaten (6.9 fruits per treefrog in average).
As there were no insects inside the terraria, the
hypothesis that insects might be functioning as
the real attractant can be rejected. In the field
we observed one H. truncata eating a fruit of E.
ovalifolium: the frog simply snapped and swal-
Fig. 1. Hyla
truncata,
the fruit-eating
treefrog, on
a fructifying
shrub of Erythroxylum ovalifolium.
lowed the fruit. Two H. truncata were main-
tained in captivity for 4 mo on a diet exclusively
of fruits of A. harrisii and subsisted on it.
Twenty-six untreated seeds of A. harrisii, 15
obtained from the feces of captive frogs, and
11 from ripe fruits germinated in the labora-
tory, and were considered viable when the rad-
icle appeared. Therefore, because seeds of A.
harrisii that have passed through the digestive
tract ofH. truncata are viable, this treefrog may
disperse this plant species. Seed dispersal by am-
phibians has not been reported previously (Pijl,
1969; Duellman and Trueb, 1986).
Although we do not have enough informa-
tion about the microclimate in the Restinga de
Barra de Marica, we suppose that as H. truncata
probably defecates in the axils of N. cruenta, the
chances of germination are increased in relation
to seeds dropped on the sandy soil, frequently
drier than the inside of the bromeliads. We are
now evaluating actual seed dispersal and the
nutritional value of fruits in the diet of H. trun-
cata.
Acknowledgments.-C. J. Tribe, I. Sazima, and
D. M. Teixeira reviewed the manuscript. A. R.
Melgarejo made the photograph. J. A. F. da
Costa confirmed the plant identifications. This
research was conducted during receipt of CNPq
and CEPG/UFRJ Grants by the authors.
782

HERPETOLOGICAL NOTES
HERPETOLOGICAL NOTES
LITERATURE CITED
ALEXANDER,
T. R. 1964. Observations on the feed-
ing behavior
ofBufo
marinus
(Linne).
Herpetologica
20:255-259.
DUELLMAN,
W. E., AND
L. TRUEB. 1986. Biology of
amphibians.
McGraw-Hill Book
Co., Inc.,
New York,
New York.
HAY,J. D., L. D. DE LACERDA, AND A. L. TAN. 1981.
Soil cation increase in a tropical sand dune eco-
system due to a terrestrial bromeliad. Ecology 62:
1392-1395.
HEDEEN,
S. E. 1972. Food and feeding behavior of
the mink frog, Rana septentrionalis
Baird, in Min-
nesota. Amer. Midl. Nat. 88:291-300.
IZECKSOHN,
E. 1971 Sobre a distribuicao de alguns
anfibios anuros descritos da Baixada Fluminense,
Estado do Rio de Janeiro, Brasil. Arq. Univ. Fed.
Rur. Rio de Janeiro 1:5-7.
KORSCHGEN, L. J., AND D. L. MOYLE. 1955. Food
habits
of the bullfrog
in central
Missouri
farm
ponds.
Amer. Midi. Nat. 54:332-341.
LACERDA, L. D. DE, ANDJ. D. HAY. 1982. Habitat of
Neoregelia
cruenta
(Bromeliaceae)
in coastal sand
dunes of Marica,
Brazil. Rev. Biol. Trop. 30:171-
173.
LINZEY,
D. W. 1967. Food of the leopard frog Rana
p. pipiens,
in central New York. Herpetologica 23:
11-17.
NIMER,
E. 1972. Climatologia da regiao sudeste do
Brasil.
Rev. Bras. Geog. 34:3-48.
PIJL, L. VAN DER. 1969. Principles of dispersal in
higher plants. Springer-Verlag,
Berlin, West Ger-
many.
RIZZINI,
C. T. 1979. Tratado de fitogeografia do
Brasil.
Aspectos sociologicos
e floristicos.
Hucitec-
Edusp,
Sao Paulo, Brazil.
TYLER,
M. J. 1958. On the diet and feeding habits
of the edible frog (Rana esculenta
L.). Proc. Zool.
Soc. London 131:583-595.
WINSTON,
R. M. 1955. Identification and ecology of
the toad Bufo
regularis. Copeia 1955:293-302.
ZUG, G. R., E. LINDGREN, AND J. R. PIPPET. 1975.
Distribution and ecology of the marine toad, Bufo
marinus,
in Papua
New Guinea. Pac. Sci. 29:31-50.
HELIO R. DA SILVA, MONICA C. DE BRITTO-
PEREIRA,
AND ULISSES
CARAMASCHI,
Depar-
tamento de Vertebrados,
Museu Nacional do Rio
deJaneiro, Quinta da Boa Vista, 20.942, Rio de
Janeiro, RJ, Brasil. Accepted 21 Oct. 1988.
Copeia, 1989(3), pp. 783-788
? 1989 by the American Society of
Ichthyologists and Herpetologists
THE INTERRELATIONSHIPS OF LATI-
CAUDINE SEA SNAKES BASED ON THE
AMINO ACID SEQUENCES OF SHORT-
LITERATURE CITED
ALEXANDER,
T. R. 1964. Observations on the feed-
ing behavior
ofBufo
marinus
(Linne).
Herpetologica
20:255-259.
DUELLMAN,
W. E., AND
L. TRUEB. 1986. Biology of
amphibians.
McGraw-Hill Book
Co., Inc.,
New York,
New York.
HAY,J. D., L. D. DE LACERDA, AND A. L. TAN. 1981.
Soil cation increase in a tropical sand dune eco-
system due to a terrestrial bromeliad. Ecology 62:
1392-1395.
HEDEEN,
S. E. 1972. Food and feeding behavior of
the mink frog, Rana septentrionalis
Baird, in Min-
nesota. Amer. Midl. Nat. 88:291-300.
IZECKSOHN,
E. 1971 Sobre a distribuicao de alguns
anfibios anuros descritos da Baixada Fluminense,
Estado do Rio de Janeiro, Brasil. Arq. Univ. Fed.
Rur. Rio de Janeiro 1:5-7.
KORSCHGEN, L. J., AND D. L. MOYLE. 1955. Food
habits
of the bullfrog
in central
Missouri
farm
ponds.
Amer. Midi. Nat. 54:332-341.
LACERDA, L. D. DE, ANDJ. D. HAY. 1982. Habitat of
Neoregelia
cruenta
(Bromeliaceae)
in coastal sand
dunes of Marica,
Brazil. Rev. Biol. Trop. 30:171-
173.
LINZEY,
D. W. 1967. Food of the leopard frog Rana
p. pipiens,
in central New York. Herpetologica 23:
11-17.
NIMER,
E. 1972. Climatologia da regiao sudeste do
Brasil.
Rev. Bras. Geog. 34:3-48.
PIJL, L. VAN DER. 1969. Principles of dispersal in
higher plants. Springer-Verlag,
Berlin, West Ger-
many.
RIZZINI,
C. T. 1979. Tratado de fitogeografia do
Brasil.
Aspectos sociologicos
e floristicos.
Hucitec-
Edusp,
Sao Paulo, Brazil.
TYLER,
M. J. 1958. On the diet and feeding habits
of the edible frog (Rana esculenta
L.). Proc. Zool.
Soc. London 131:583-595.
WINSTON,
R. M. 1955. Identification and ecology of
the toad Bufo
regularis. Copeia 1955:293-302.
ZUG, G. R., E. LINDGREN, AND J. R. PIPPET. 1975.
Distribution and ecology of the marine toad, Bufo
marinus,
in Papua
New Guinea. Pac. Sci. 29:31-50.
HELIO R. DA SILVA, MONICA C. DE BRITTO-
PEREIRA,
AND ULISSES
CARAMASCHI,
Depar-
tamento de Vertebrados,
Museu Nacional do Rio
deJaneiro, Quinta da Boa Vista, 20.942, Rio de
Janeiro, RJ, Brasil. Accepted 21 Oct. 1988.
Copeia, 1989(3), pp. 783-788
? 1989 by the American Society of
Ichthyologists and Herpetologists
THE INTERRELATIONSHIPS OF LATI-
CAUDINE SEA SNAKES BASED ON THE
AMINO ACID SEQUENCES OF SHORT-
CHAIN NEUROTOXINS.-Sea snakes are a
group of approx. 50 species of highly venomous
marine snakes of the family Elapidae. It has long
been recognized that the sea snake genus Lat-
icauda Laurenti, known commonly as "sea
kraits," is distinct phenetically and phylogenet-
ically from the other sea snakes. Laticaudines
differ from other sea snakes in possession of
several primitive, terrestrial elapid character
states: oviparity, anterolateral placement of the
nostrils, enlarged ventral scales, and lack of nos-
tril flaps. These features suggest that Laticauda
is less well adapted to marine life than other sea
snakes and, in fact, these species are the most
terrestrial of all sea snakes.
Four nominal species of sea kraits are rec-
ognized. Laticauda laticaudata Linnaeus is a wide-
ranging species comprised of two subspecies: L.
laticaudata laticaudata Linnaeus from the Phil-
ippine Islands, Indo-Australian Archipelago,
New Guinea, Australia and Oceania (McCarthy,
1986) and L. 1. affinis Anderson from India, the
Malay Peninsula, South China, Taiwan and Ja-
pan (McCarthy, 1986). Laticauda colubrina
Schneider is also wide-ranging, almost match-
ing the distribution ofL. laticaudata (McCarthy,
1986), but with several occurrences reported in
the eastern Pacific along the coast of the Neo-
tropics (Villa, 1962; Alvarez del Toro, 1982).
Laticauda crockeri
Slevin is a form endemic to
Lake Te-Nggano of Rennell Island in the Sol-
omon Islands. It is so similar to L. laticaudata
that its status as a species is problematical
(McCarthy, 1986). Finally, L. semifasciata
Rein-
wardt in Schlegel has a disjunct distribution
(McCarthy, 1986). Western populations are
found from southern Japan southward to the
Lesser Sunda Islands; eastern populations are
centered around the islands of Niue, Tonga and
Samoa. Formerly, the eastern populations were
considered to be a fifth species, L. schistorhynchus
Gunther, but there is considerable evidence that
L. semifasciata
and L. schistorhynchus
are conspe-
cific (Guinea et al., 1983; Tamiya et al., 1983).
The four species of Laticauda form a mono-
phyletic group as shown by such synapomor-
phies as an infolded nasal vestibulum (Mc-
Carthy, 1986).
Of the recent studies dealing with the phy-
logenetic relationships oflaticaudines, only those
of Voris (1977) and McCarthy (1986) have ad-
dressed relationships within the genus. Using
morphological data, Voris (1977) found syn-
apomorphies supporting the following relation-
ships: ([L. laticaudata, L. colubrina] L. semifasci-
CHAIN NEUROTOXINS.-Sea snakes are a
group of approx. 50 species of highly venomous
marine snakes of the family Elapidae. It has long
been recognized that the sea snake genus Lat-
icauda Laurenti, known commonly as "sea
kraits," is distinct phenetically and phylogenet-
ically from the other sea snakes. Laticaudines
differ from other sea snakes in possession of
several primitive, terrestrial elapid character
states: oviparity, anterolateral placement of the
nostrils, enlarged ventral scales, and lack of nos-
tril flaps. These features suggest that Laticauda
is less well adapted to marine life than other sea
snakes and, in fact, these species are the most
terrestrial of all sea snakes.
Four nominal species of sea kraits are rec-
ognized. Laticauda laticaudata Linnaeus is a wide-
ranging species comprised of two subspecies: L.
laticaudata laticaudata Linnaeus from the Phil-
ippine Islands, Indo-Australian Archipelago,
New Guinea, Australia and Oceania (McCarthy,
1986) and L. 1. affinis Anderson from India, the
Malay Peninsula, South China, Taiwan and Ja-
pan (McCarthy, 1986). Laticauda colubrina
Schneider is also wide-ranging, almost match-
ing the distribution ofL. laticaudata (McCarthy,
1986), but with several occurrences reported in
the eastern Pacific along the coast of the Neo-
tropics (Villa, 1962; Alvarez del Toro, 1982).
Laticauda crockeri
Slevin is a form endemic to
Lake Te-Nggano of Rennell Island in the Sol-
omon Islands. It is so similar to L. laticaudata
that its status as a species is problematical
(McCarthy, 1986). Finally, L. semifasciata
Rein-
wardt in Schlegel has a disjunct distribution
(McCarthy, 1986). Western populations are
found from southern Japan southward to the
Lesser Sunda Islands; eastern populations are
centered around the islands of Niue, Tonga and
Samoa. Formerly, the eastern populations were
considered to be a fifth species, L. schistorhynchus
Gunther, but there is considerable evidence that
L. semifasciata
and L. schistorhynchus
are conspe-
cific (Guinea et al., 1983; Tamiya et al., 1983).
The four species of Laticauda form a mono-
phyletic group as shown by such synapomor-
phies as an infolded nasal vestibulum (Mc-
Carthy, 1986).
Of the recent studies dealing with the phy-
logenetic relationships oflaticaudines, only those
of Voris (1977) and McCarthy (1986) have ad-
dressed relationships within the genus. Using
morphological data, Voris (1977) found syn-
apomorphies supporting the following relation-
ships: ([L. laticaudata, L. colubrina] L. semifasci-
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