Leptodactylus pascoensis Heyer 1994

Leptodactylus pascoensis

HOLOTYPE.—LACM 40665, an adult male from Peru; Pasco; Iscozazin Valley, Chontilla, 780 m, ∼10°17′S, 75°13′W. Collected by Richard Etheridge and David B. Wake, 13 Aug 1961.

PARATOPOTYPES.—All collected by Richard Etheridge: LACM 40660, 9 Jul 1961; LACM 40661–40663, USNM 313875, 11 Aug 1961.

DIAGNOSIS.—Leptodactylus pascoensis presently is known only from a restricted region along the amazonian flanks of the Andes in central Peru. Other Leptodactylus with toe fringes (other than L. ocellatus and its closest relatives) that might be expected to occur near or with pascoensis are L. bolivianus, diedrus, griseigularis, leptodactyloides, petersii, and wagneri. Dorsolateral folds in L. pascoensis are never long nor do pascoensis have distinct lip stripes; all bolivianus have long dorsolateral folds and many individuals have distinct light lip stripes. Leptodactylus pascoensis is larger than diedrus (pascoensis females 52–67 mm SVL, males 60–61 mm SVL; diedrus females 34–48 mm SVL, males 30–40 mm SVL), and the ventral and posterior thigh patterns merge in pascoensis whereas they abut in diedrus. Leptodactylus pascoensis is also larger than griseigularis (griseigularis females 39–58 mm SVL, males 35–51 mm SVL). The commonest light posterior lip stripe condition in pascoensis is with no indication of stripes; the commonest condition in griseigularis is indistinct. Leptodactylus pascoensis is larger than leptodactyloides as well (leptodactyloides females 35–56 mm SVL, males 28–48 mm SVL), and most pascoensis individuals have mottled posterior thigh surfaces with no indication of light stripes, whereas leptodactyloides individuals usually have at least some indication of light posterior thigh stripes. Leptodactylus pascoensis is larger than petersii (petersii females 31–51 mm SVL, males 27–41 mm SVL), and the belly is never extensively mottled in an anastomotic pattern whereas most petersii have extensively patterned bellies and often in an anstomotic pattern. No L. pascoensis have long dorsolateral folds; the commonest condition in wagneri is long dorsolateral folds. The bellies of L. pascoensis are lightly to moderately mottled, but never in a bold mottle; the bellies of most wagneri are moderately mottled and some are extensively mottled, and the bellies are often with a boldly mottled pattern, approaching an anastomotic pattern.

DESCRIPTION OF HOLOTYPE.—Snout rounded from above, rounded in profile; canthus rostralis indistinct; lores weakly obtuse-concave in cross section; tympanum large, diameter about eye diameter; vocal slits well developed, parallel to posterior of lower jaw; vocal sac single, internal, no external modification visible; vomerine teeth in two long, almost abutting arched series extending posterior to choanae, from midchoana to midchoana; finger lengths II≈IV
SVL 60.3 mm, head length 20.8 mm, head width 21.8 mm, tympanum diameter 4.7 mm, thigh length 25.1 mm, shank length 27.0 mm, foot length 31.6 mm.

Dorsum almost uniform brown with faint pattern of light interorbital bar bordered behind by darker interorbital triangular blotch, rest of dorsum with larger and smaller darker blotches, upper lip with medial light bar, two light vertical lip bars between naris and eye, somewhat distinct light stripe from posterior corner of eye, under tympanum through jaw commissure, upper limbs very weakly cross barred or spotted; chin and throat with somewhat ill-defined light spots on a darker ground, belly with only a very few scattered melanophores; posterior surface of thigh boldly mottled dark brown and almost white, no real indication of light stripes.

ETYMOLOGY.—Named for the Peruvian Department of Pasco, where most of the known specimens have been collected.

ADULT CHARACTERISTICS (N = 4 females, 3 males).—Posterior light lip stripes somewhat distinct or not discernible, when discernible stripes extending from posterior corner of eye; posterior thigh light stripe indistinct or usually not discernible; dorsolateral folds (apparently) absent, short, or medium length; toe tips just swollen or swollen; male black thumb spines large; chin/throat with light spots on a darker field or usually absent; belly lightly to moderately mottled.

Females 52.4–66.6 mm SVL, males 60.3–61.4 mm SVL; female head length 33%–36% SVL, male head length 34%–37% SVL; female head width 34%–36% SVL, male head width 36%–39% SVL; female tympanum diameter 7%–8% SVL, male tympanum diameter 8%–9% SVL; female thigh length 41%–47% SVL, male thigh length 42%–47% SVL; female shank length 47%–49% SVL, male shank length 45%–50% SVL; female foot length 53%–56% SVL, male foot length 52%–53% SVL.

HABITAT AND COLOR

Leptodactylus pascoensis is a species of frog in the family Leptodactylidae. It is endemic to Peru where it is only known from two localities ((Chontilla, Pasco, and Serrania de Sira, Huánuco)). It is an inhabitant of forest floor of the Amazonian flanks of the Andes. Reproduction takes place in foam nests in temporary ponds.

Leptodactylus pascoensis is not an uncommon species but its range is small and it suffers from habitat loss caused by increased agricultural activity.

Male Leptodactylus pascoensis grow to a snout–vent length of 60–61 mm (2.4–2.4 in) and females to 52–67 mm (2.0–2.6 in).