Rhinella leptoscelis Boulenger 1912
Creators: name: Padial, José M.
name: Chaparro, Juan C.
name: Köhler, Jörn
name: Riva, Ignacio De La
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Amphibia
Anura
Bufonidae
Rhinella
Rhinella leptoscelis

description: Rhinella leptoscelis (Boulenger, 1912)
Bufo leptoscelis Boulenger, 1912, Ann. Mag. Nat. Hist., Ser. 8, 10: 186. Holotype (Fig. 1 A–B): BM 1907.5.7.32. Type locality: "Santo Domingo, Carabaya, S.E. Peru, 6500 feet ".
Diagnosis. A medium-sized species of Rhinella (Figs. 1 A–B, 2A–G) distinguished by the following unique combination of characteristics: (1) canthus rostralis concave in dorsal view, sharp in profile, orbitotympanic and postorbital crests prominent, not protruding; (2) tympanum distinct, oval; (3) parotoid glands large, oblong to subtriangular, protuberant, separated from eyelid and tympanum by the supratympanic crest; (4) body surfaces covered by spiny tubercles with keratinized tips; (5) extremities long and slender; (6) a dorsolateral row of conical, enlarged, and elevated tubercles; (7) tarsal fold absent; (8) webbing absent on fingers, basal and serrated between toes; (9) first finger longer than second; (10) iris green in life.
From other species of the Rhinella veraguensis species group, R. leptoscelis can be distinguished as follows. From R. amboroensis, R. arborescandens, R. justinianoi, R. quechua and R. veraguensis (Fig. 1 C–D) by having a conspicuous tympanic membrane and toe webbing basal and serrated. From R. arborescandens, R. chavin, R. manu, R. multiverrucosus, R. nesiotes, R. rumbolli, and R. tacana by lacking fleshy interdigital membranes, having fingers slender with first finger longer than second, and subtriangular parotoids. From R. chavin and R. multiverrucosus it can be distinguished by lacking glands on the forearms and hind legs. Rhinella leptoscelis shares with R. fissipes the slender fingers and serrated basal membrane on toes. However, R. leptoscelis can be distinguished from R. fissipes by having cranial crests, conspicuous tympanic membrane, and larger tubercles on dorsal skin. With R. inca, R. leptoscelis shares the presence of cranial crests, first finger longer than second, and the observable tympanic membrane, but R. leptoscelis has more spiny dorsal skin and serrated fringes, and prominent cranial crests anterior and posterior to eye (absent in R. inca). From Rhinella margaritifera and R. stanlaii, two members of the R. margaritifera group inhabiting the Andean slopes from Southern Peru to Central Bolivia, R. leptoscelis can be distinguished by lacking a protruding cranial crest above the tympanic area.
Redescription of the holotype. An adult female (Fig. 1 A–B) with long and slender extremities; large and flat head, wider than long, its width 36% of SVL, its length 29% of SVL; snout subacuminate in dorsal view, round in profile; cranial crests present, occipital and orbitotympanic crests well developed but not protruding; skin of head not co-ossified with underlying cranial bones; internarial area concave; nostrils not protuberant, very small, oriented laterally; canthus rostralis narrow and elevated in profile, concave in dorsal view; lips flat; eye-nostril distance smaller than eye length; tympanic membrane visible, conspicuous, oval, surrounded by tubercles, its diameter approximately half of eye length; tympanic annulus thin, overlapped with surrounding granules. Forelimbs long and slender; hand broad, with long and slender fingers; relative length of fingers II<III<I<IV; webbing absent, lateral fringes present, serrated; tips of digits round, not expanded; ulnar region covered by keratinized spines; palmar tubercle subtriangular, protruding; prepollical tubercle elongated, protruding, smaller than palmar tubercle; subarticular tubercles round, conspicuous; supernumerary tubercles conical, diffuse, smaller than subarticular tubercles. Hind limbs and feet long; tibia length 45% of SVL; foot length 44% of SVL; no tarsal fold, tarsus covered by spines; outer metatarsal tubercle round, prominent, 1/2 the size of inner; inner metatarsal tubercle small, prominent, elongate; relative length of toes I<II≤V<III<IV; webbing basal between toes I–II, II–III, and IV–V, slightly more developed between III–IV, reaching the basis of second subarticular tubercle of toe III; tip of toes rounded; subarticular tubercles prominent, round to ovoid, larger than supernumerary tubercles; supernumerary tubercles abundant, small, conical or rounded. Choanae, vomerine teeth, and tongue conditions were not examined in the holotype to avoid damaging of the specimen (but see below).
Skin of head, body, and extremities bearing abundant conical tubercles with keratinized tips; enlarged tubercles forming an irregular dorsolateral row on each side of dorsum; canthus rostralis, interorbital region, and snout with scarce or no tubercles; parotoid glands large (60% HL), subtriangular, more displaced to side of the head than to dorsum, almost in contact with tympanic membrane, and in contact with small, short orbitotympanic and postorbital crest; enlarged glands absent on limbs or forearms; skin on throat and other ventral surfaces granular to spiny. In preservative, dorsum and ventral surfaces mostly dark reddish-orange, head, belly and fingers paler.
Measurements (in mm) are only available for adult females. Measurements of the holotype (BM 1947.2.21.95) are followed in parentheses by those of additional specimens (MHNC 5976, 5989, and 5975, respectively): SVL, 53.5 (85.5, 56.8, 59.8); HL, 15.4 (23.3, 17.4, 19.1); HW, 19.2 (29.3, 20.8, 19.9); ED, 6.5 (6.9, 5.9, 6.9); END, not measured (5.8, 4.2, 5.6); EW, 3.8 (6.0, 4.8, 4.9); IND, not measured (5.2, 3.7, 3.8); IOD, not measured (10.9, 8.6, 7.0); TL, 24.0 (37.1, 30.4, 28.2); FL, 23.5 (34.5, 27.1, 27.2). These measurements indicate a large variation in adult female size, from 56.8–85.5 in SVL.
Variation. We describe variation in qualitative characters, measurements, and color in life on the basis of five newly collected specimens from the type locality (MHNC 5975–6, 5987–9; see associated data under remarks section). No male specimens of R. leptoscelis have been found to date. The holotype and the five new Peruvian specimens show few differences in qualitative characters (Fig. 1 A–B and Fig. 2 A–G), mostly related to skin texture and coloration. The largest adult female (MHNC 5976; Fig. 2 B) has spiny skin texture. The choanae and vomerine teeth were examined in an adult female with convoluted oviducts (MHNC 5975). The choanae are large, round, and anterolateral; between them are the odonthophores, which are no more than two tiny, almost indiscernible protuberances lacking vomerine teeth. Dorsal coloration is brownish-grey in MHNC 5976 and brownish-orange in MHNC 5975, with a longitudinal middorsal pale yellow stripe (this stripe is underlined with black in MHNC 5976). The dorsolateral row of tubercles is brownish-cream in MHNC 5976 and intense orange in MHNC 5975. The flanks are pale grey with darker spots in MHNC 5976, and orange and grey with tiny dark grey spots and white tubercles in MHNC 5975. In MHNC 5976, the lateral surfaces of head are overall dark brownish-grey, with pale lips; dorsally, the eyelids and the interorbital region are brownish-orange to cream, with two black spots posteriorly, and a longitudinal cream stripe; the occipital region has two large yellow and bold black spots. In MHNC 5975, the head is overall orange, with a middorsal longitudinal yellow stripe; the ventral regions have black, white, orange and grey flecks; the plantar surfaces are dark brownish-grey, with yellowish-cream fringes and membranes. The hind limbs are dark grey with two transversal cream to yellow narrow irregular stripes in MHNC 5976, and brownish-orange with grayish-brown transversal bars in MHNC 5975. The forelegs are dark grey with some darker and paler spots in MHNC 5976, and brownish-orange with grayish-brown transversal bars in MHNC 5975. Bolivian specimens (see below) are also all females, with a light vertebral stripe, bordered by dark brown lines, and cream lateral dorsum and flanks, contrasting with the darker mid-dorsum (Fig. 2 F). Dark brown dorsal flecks and markings are present in all Bolivian specimens. The throat is dark brown with some scattered cream spots (Fig. 2 G).
Remarks. Other specimens that we now consider to represent R. leptoscelis are those reported as R. fissipes by Köhler (2000) for Bolivia. The identity of these Bolivian populations was reinvestigated and some differences between the R. fissipes holotype and Bolivian specimens (i.e. tympanum condition) mentioned by Köhler (2000), and the lack of distinct cranial crests in R. fissipes, seem to be reliable characters to distinguish between both taxa. Consequently, R. leptoscelis, and not R. fissipes should now be listed for Bolivia, although the presence of the latter in the country is very likely.
Distribution. Since the discovery of Rhinella leptoscelis by Ockenden at the end of the Nineteenth Century at Santo Domingo de Carabaya, Puno, Peru (2000 m a.s.l.) (Fig. 3), no additional specimens were allocated to this species. One of the authors (JCC) rediscovered this species during an expedition to the type locality and the surrounded area in November 2006. He collected two specimens (MHNC 5975–6) at Santo Domingo de Carabaya, 1658 m a.s.l., and three specimens (MHNC 5987–9) at a lower altitude, 1400 m a.s.l. (see Appendix). More recently, we collected additional specimens of R. leptoscelis (Fig. 2 C) in Kimbiri River, Vilcabamba Mountains, Cusco, Peru (Fig. 3; Appendix).
Bolivian records of R. leptoscelis (see above) come from Chapare, 1300–1400 m a.s.l., Departamento Cochabamba, and from the surroundings of Caranavi, Departamento La Paz, Bolivia (the latter specimens, deposited at CBF, were erroneously reported as originating from Rurrenabaque, Departamento Beni, by Köhler 2000).
Thus, Rhinella leptoscelis occurs in well-preserved humid montane forests from the Chapare region in Bolivia to the Vilcabamba mountain range in southern Peru. All known specimens were found between 1300–1658 m. The species is known to occur in sympatry with R. veraguensis and R. fissipes at the type locality, with R. inca in Vilcabamba, and with B. quechua, R. stanlaii, and R. veraguensis in the Bolivian Chapare region.
description: Published as part of Padial, José M., Chaparro, Juan C., Köhler, Jörn & Riva, Ignacio De La, 2009, Rediscovery, resurrection and redescription of Rhinella leptoscelis (Boulenger, 1912) (Anura: Bufonidae), pp. 56-64 in Zootaxa 2115 on pages 57-61, DOI: 10.5281/zenodo.274890