Phrynopus peruanus Peters

Lehr, Edgar, 2007, Rediscovery of Phrynopus peruanus Peters 1874 (Amphibia, Anura, Leptodactylidae), Zootaxa 1485, pp. 51-57 : 52-56

Phrynopus peruanus Peters

Characteristics (based on two males: MHNSM 19978, MTD 46802, two females: MHNSM 19977, MTD 46801, and three syntypes: ZMB 7707). A species of Phrynopus having (1) skin on dorsum tuberculate with tubercles coalesced into ridges dorsally and dorsolaterally; skin on venter areolate; discoidal fold obscure; dorsolateral folds absent; (2) tympanic membrane and tympanic annulus evident, vertically ovoid, its length slightly less than half length of eye; (3) snout short, rounded in dorsal view, rounded above and slightly inclined anteroventrally in profile ( Fig. 1 A, B); (4) upper eyelid lacking tubercles, narrower than interorbital distance; cranial crests absent; (5) dentigerous processes of vomers round; (6) vocal sac present, vocal slits absent, nuptial pads present on Finger I; (7) Finger I shorter than Finger II; tips of digits rounded, not expanded ( Fig. 1 C); (8) fingers lacking lateral fringes; (9) ulnar tubercles absent; (10) heel and tarsus lacking tubercles and folds; (11) inner metatarsal tubercle ovoid, approximately equal in size to ovoid outer metatarsal tubercle; plantar supernumerary tubercles absent ( Fig. 1 D); (12) toes lacking lateral fringes; webbing absent; Toe V slightly shorter than Toe III; tips of digits rounded; (13) dorsum mottled brownish olive and black; venter mottled pale gray and blackish brown; in females, inside of lower arms, axilla, groin, and concealed surfaces of shanks orange; (24) SVL in males 22.1–22.5 mm, in females 23.3–30.0 mm. See table 1 for measurements and proportions.

Coloration in life. The dorsum of a male (MHNSM 19978, Fig. 2 ) was mottled brownish olive and black with a narrow, discontinuous, tan middorsal stripe; the groin and venter was mottled pale gray and blackish brown; the iris was greenish gold with black reticulations. The dorsum in the other male (MTD 46802) was tan with less black, but was otherwise colored as mentioned above.

The dorsum of a female (MHNSM 19977, Fig. 3 ) was brownish olive with tubercles and ridges outlined with blackish brown; the venter was pale gray with blackish-brown blotches on chest and on belly; the thighs were blackish brown; the median surfaces of the forearms, axilla, groin, and concealed surfaces of shanks were orange, and orange blotches were on the proximal ventral surface of the tarsus; the upper half of iris was greenish gold with black reticulations, and the lower half was black. The other female (MTD 46801) differed in having a narrow, tan middorsal stripe. Orange coloration was restricted to females.

Distribution and ecology. Phrynopus peruanus is only known from the type locality in the Cordillera Oriental in the puna of Maraynioc at 3825 m a.s.l. ( Fig. 4) in the Vitoc Valley (11° 21' 35.2" S, 75° 28' 52.6" W). Males and females were found inside bunches of Peruvian Feather Grass ( Stipa icchu ) next to a small creek in a swampy area during the early afternoon (13–14.00 h) on 13–14 December 2005 ( Fig. 5 ). Males were calling from inside the bunches of grass.

46801, males: MHNSM 19978, MTD 46802) ranges followed by means and one standard deviation in parentheses. P. peruanus

Remarks. Phrynopus peruanus is sexually dimorphic in dorsal skin texture and coloration: the dorsum in males is tuberculate with tubercles coalescing into prominent ridges dorsally and dorsolaterally, whereas tubercles and ridges are less prominent in females. Lynch (1975) correctly assumed the smooth skin in the two individuals observed by him to be an artifact of preservation. Peters (1874) characterized the skin texture as “etwas uneben” (a little uneven). The other Peruvian Phrynopus with sexually dimorphic coloration is P. pesantesi . Males of that species have yellow blotches on the throat, belly, groin, and ventral surfaces of the limbs, whereas females lack yellow coloration (Lehr et al., 2005; Lehr, 2006). Male P. w e t t s t e i n i have a black throat (Lehr, 2006). Another frog inhabiting Peruvian Feather Grass is Eleutherodactylus ( Lehr and Duellman, 2007) . Peruvian Feather Grass is the typical vegetation of higher elevations in the Andes of Peru. The dense grass provides humidity and hiding places. Presumably, P. peruanus deposits eggs inside the grass. Stipa icchu traditionally is used by the indigenous people for roofing. Frequently it is burned so as to fertilize fields. Therefore, anurans depending on this plant may be locally threatened. Herpetologists doing fieldwork in the puna should pay special attention to the Peruvian Feather Grass as a potential habitat for anurans.

Phrynopus peruanus is restricted to puna habitats of the Vitoc Valley at Maraynioc. Specimens were found only at the collecting site described herein. Because of its location next to the road leading to Maraynioc, it is likely that this site is the type locality of the species. Although calls were easily heard from the road, specimens were difficult to localize and to catch inside the dense grass. Given the small area of occurrence (less than 100 km 2 by estimation), the proposed IUCN criterium following IUCN (2001) for Phrynopus peruanus is critically endangered.

Specimens referred to as P. montium from Maraynioc (e.g., Duellman, 2000; Lehr et al., 2005) revealed to be a new species, which will be described elsewhere. In contrast to P. peruanus this species is restricted to lower elevations in cloud forest habitats of the Vitoc Valley, next to the village of Maraynioc.

Figures

FIGURE 1. Dorsal (A) and lateral (B) views of head and ventral views of hand (C) and foot (D) of Phrynopus peruanus (MHNSM 19977, SVL 27.5 mm).

FIGURE 2. Dorsal (A) and ventral (B) views of male Phrynopus peruanus (MHNSM 19978, SVL 22.5 mm).

FIGURE 3. Dorsal (A) and ventral (B) views of female Phrynopus peruanus (MHNSM 19977, SVL 27.5 mm).

FIGURE 5. Habitat of Phrynopus peruanus.