The Amphibians and Reptiles of Sinaloa, Mexico - Smithsonian ...

AMPHIBIANS AND REPTILES OF SINALOA, MEXICO 75
Distribution in Sinaloa.—Known from the foothills below 1200
meters in southern Sinaloa and from near Choix in the north. See
Fig. 15.
Specimen examined.—16 km. NNE Choix, 520 m. (° KU 738X2); 2.4 mi.
E Chupaderos (JFC 62:72-73); 1 mi. W Copak (CSCLB 1668-69); 1 mi.
E Panuco (CSCLB 1667); Plomosas, 760 mm. ("KU 73814-16); 0.4 mi.
E Potrerillos (JFC 62:14-15); Santa Lucia, 1100 m. ("KU 75251; CSCLB
1671-72); 2.2 km. NE Santa Lucia, 1150 m. ('KU 78256); 2.4 km, E Santa
Lucia {KU 44555); 2-3 km. E Santa Luck ("KU 41530-41, 41558-60,
44556-59); 3 mi. E. Santa Lucia (CSCLB 1670); 5 km. SW Santa Lucia,
660m. ("KU 80686); 4.0 mi. W Santa Lucia (JFC 62:1-3).
Literature record.—18 mi. NE Coneoidia (Webb, 1960:289).
Additional records.—10.7 mi. N Coneoidia (MCZ 32577-79); 1.3 mi. N
Santa Lucia (MCZ 32580-81); 24.8 mi. E (by highway 40) Junction highway
15 and 40 (Villa Union) (CAS 99302-09).
Leptodactylus occidentalis Taylor
Leptodactylus occidentalis Taylor, Trans. Kansas Acad. Sci., 39:349, 1937
(type locality, Tepic, Nayarit).
Remarks.—From Leptodactylus melanonotus, L. occidentalis usually
differs as follows: head narrower at eye level; tympanum
smaller; throat and chest lightly pigmented with black and dark
brown (instead of heavily pigmented with dark gray); ventral
glands dark brown or black, sharply defined, absent from the throat,
and absent or reduced on the mid-ventral surface. A re-evaluation
of the importance of these characters is considered necessary, especially
with reference to the ventral glands,
Duellman (1961:32) suggested that size might be another valid
character for separating these two species. The average snout-vent
length in samples of adult males from Sinaloa (16), Veracruz (5),
Campeche (9), Guatemala (8), Nicaragua (10), Costa Rica (21),
and Panama (9) varied from 32 to 36 mm. No geographic trend in
size was noticed.
Three specimens (LACM 6207, 6221, 6222) from the southern
lowlands are intermediate between the two nominal species in the
position and color of the ventral glands. Duellman (1961:33)
mentioned L, melanonotus from Acaponeta, Nayarit. If he is correct
in the allocation of the Acaponeta frogs, then it is possible that
populations of Leptodactylus from southern Sinaloa are intermediate
between the two recognized species. Because of the lack of material
from the critical region, we refer all Leptodactylus from Sinaloa to
L. occidentalis.
During the dry season individuals were found beneath rocks
along streams, near wells, and in moist canyons. In the rainy