Pristimantis sneiderni, Ospina-Sarria & Duellman, 2019

Ospina-Sarria, Jhon Jairo, 2019, Two New Species of Pristimantis (Amphibia: Anura: Strabomantidae) from Southwestern Colombia, Herpetologica 75 (1), pp. 85-95 : 89-93

Pristimantis sneiderni sp. nov.

( Figs. 5A,B , 6A,B ; Table 2 )

Holotype. — KU 145021 , adult female from the Laguna San Rafael, 3450-m elevation (2°23 ′ N, 76°19 ′ W; datum ¼ WGS84), Departamento del Cauca, Colombia, one of a series collected by Kjell von Sneidern in December 1938.

Paratypes. — KU 145019–20 , 145022 , adult males collect-ed with the holotype .

Diagnosis. — Pristimantis sneiderni is diagnosed by the following combination of characters: (1) skin on dorsum bearing low warts (most obvious on flanks); ventral skin areolate; discoidal fold present, well anterior to groin; dorsolateral folds and ridges absent in scapula region; (2) tympanic membrane not evident; tympanic annulus present, its upper edge covered by supratympanic fold, extending only just posterior to tympanic annulus; (3) snout round in dorsal view and in profile, with papilla at the tip (most obvious in males); canthus rostralis concave; (4) upper eyelid warty, narrower than IOD (50.0–80.0% IOD); interocular tubercle absent; cranial crests absent; (5) choanae small, ovoid; not concealed by palatal shelf of maxillary arch; dentigerous processes of vomers absent; (6) males lacking vocal slits and nuptial pads; (7) finger I shorter than finger II; discs and circumferential grooves present on all fingers; discs truncate, except on finger I, which is round; disc of finger I smaller than that of finger II and this in turn smaller than discs on fingers III and IV; (8) fingers with narrow lateral fringes; palmar tubercle divided; thenar tubercle oval, same size as palmar tubercle; supernumerary tubercles low, distributed on all fleshy parts of palm; subarticular tubercles round, prominent, two on thumb and second finger and three on third and fourth fingers, and larger than supernumerary tubercles; (9) antebrachial tubercle present; other ulnar tubercles absent; (10) heel bearing one small tubercle; outer edge of tarsus bearing low tubercles; inner tarsal fold absent; (11) inner metatarsal tubercle elongate, its length twice its width; conical outer metatarsal tubercle onefourth the size of inner metatarsal tubercle; subarticular tubercles round, prominent, two on toes I and II, three on toes III and V, and four on toe IV; supernumerary plantar tubercles low, rounded, on proximal segments of toes; (12) toes bearing narrow lateral fringes; webbing absent; toe III shorter than toe V; toe III extending to distal edge of the antepenultimate subarticular tubercle of toe IV; toe V reaching the edge distal to the penultimate subarticular tubercle of toe IV; discs and circumferential grooves present on all toes; discs of toes III – V equal to discs on fingers II– IV and larger than discs of toe I; (13) color in preservative: dorsum and flanks tan with small dark brown markings; venter tan with brown mottling, mainly on chest, canthal stripe dark brown, throat tan with fine brown spots; posterior surfaces of thighs uniformly tan; (14) males smaller than females; SVL in three adult males 21.0, 22.0, and 23.0 mm, in one adult female 28.0 mm .

Comparisons. — Pristimantis sneiderni differs from the other species in the genus by having subarticular tubercles beneath the joint between distal phalanges, dorsal skin with low warts, papilla at the tip of snout in adult males, and by lacking a tympanic membrane, dentigerous processes of vomers, and vocal slits. It is most similar to P. boulengeri and two Peruvian species, P. deŋi and P. schultei ( Figs. 5 , 6 ), by having tubercles beneath the joint between distal phalanges, dorsal skin with low scattered tubercles or warts, canthal stripe darker, papilla at tip of snout, tubercles or warts on upper eyelids, heel with one or more conical tubercles, low tubercles on medial surface of tarsus, dorsal coloration in preservative tan with darker brown markings (except P. schultei ), and by being relatively large (except P. deŋi ). From P. boulengeri , P. sneiderni is distinguished in having a round snout in profile (rather acutely round; Fig. 5B,D ), dorsal skin with low warts (rather than finely granular), and in lacking dentigerous processes of vomers and vocal slits. Pristimantis sneiderni differs from P. schultei by having a round snout in profile (rather than inclined posteroventrally; Fig. 5B,F ), and in lacking ulnar tubercles, dentigerous processes of vomers, and vocal slits. Pristimantis sneiderni is distinguished from P. deŋi by having a snout round in profile (rather than protruding and inclined posteroventrally) and in lacking weakly defined dorsolateral folds, dentigerous processes of vomers, and subgular vocal sac ( Fig. 6 ). From the genus Pristimantis , other species with similar appearance to P. sneiderni are P. acuminatus ( Shreve 1935) , P. breƲifrons ( Lynch 1981) , P. enigmaticus Ortega-Andrade et al. (2015) , P. limoncochensis Ortega-Andrade et al. (2015) , P. omeƲiridis Ortega-Andrade et al. (2015) , and P. pseudoacuminatus ( Shreve 1935) . However, P. sneiderni is distinguished from those species by lacking the dentigerous processes of vomers (dentigerous processes of vomers are present in those species). In addition, P. sneiderni differs from P. enigmaticus , P. limoncochensis , and P. omeƲiridis by lacking vocal slits (character state present in those species) and by having a dorsal skin with low warts (rather than the dorsal skin shagreened as in P. enigmaticus , or smooth as in P. limoncochensis and P. omeƲiridis ). Additional characters that distinguish P. sneiderni from P. acuminatus and P. breƲifrons are the round snout in dorsal view (rather acuminate or subacuminate in those species) and the absence of vocal slits (present in P. breƲifrons ). Finally, P. pseudoacuminatus is distinctively smaller (12.7–17.6 mm in males, 18.1–22.4 mm in females; Lynch 1980a) when compared with P. sneiderni (21.0–23.0 mm in males, 28.0 mm in the only known female).

Among species distributed on the southern portions of the Cordillera Central of Colombia, Pristimantis sneiderni could be confused with P. petersi ( Lynch and Duellman 1980) . However, P. sneiderni is larger (SVL 21.0–23.0 mm in adult males and 28.0 in one adult female) than P. petersi (SVL 14.5–19.9 in adult males and 20.3–23.1 mm in adult females; Lynch and Duellman 1980), and it lacks dentigerous processes of vomers and vocal slits (character states present in P. petersi ).

Description of the holotype. —An adult female with head slightly wider than body; head width 39.2% of SVL; HL 32.1% of SVL; snout rounded in dorsal view and in profile; eye–nostril distance 66.6% of diameter of eye; nostrils not protuberant, directed slightly anterolaterally at level of lower jaw. Canthus rostralis curved, not elevated; canthal stripe dark brown; loreal region concave lacking tubercles; lips rounded; internarial region not depressed; top of head flat; upper eyelid warty, its width 50.0% of IOD; supratympanic fold slightly curved downward only just posterior to tympanic annulus, tympanic membrane not evident, tympanic annulus present, upper fifth covered by the supratympanic fold; two nonenlarged postrictal tubercles. Choanae small, nearly round, not obscured by palatal shelf; dentigerous processes of vomers absent; tongue as long as wide, its posterior border not notched, posterior third not adherent to floor of mouth.

Skin on dorsum bearing low warts (most obvious on flanks); skin on belly and throat areolate; skin on the ventral surface of the thighs, just below the cloaca bearing low warts; skin on posteroventral surfaces of thighs smooth; discoidal fold present, well anterior to groin; dorsolateral folds absent; cloacal sheath short. Antebrachial tubercle present; other ulnar tubercles absent; palmar tubercle deeply bifid; thenar tubercle oval, as wide as palmar tubercle; subarticular tubercles round, prominent, larger than supernumerary tubercles, two on thumb and second finger and three on fingers III and IV; supernumerary tubercles low, on all the fleshy parts of the palm; fingers bearing lateral fringes; relative lengths of fingers I <II <IV <III, all fingers having terminal ventral pads well defined by circumferential grooves; disc on thumb narrow, that on finger II slightly smaller than tympanic annulus; discs on fingers III and IV slightly larger than tympanic annulus. Hind limbs moderately robust; when hind limbs flexed perpendicular to axis of body, heels overlap; tibia length 50.0% of SVL; foot length 50.0% of SVL; heel bearing one low tubercle; outer edge and medial surface of tarsus bearing low tubercles; tarsal fold absent; inner metatarsal tubercle elongate, its length twice its width; conical outer metatarsal tubercle one-fourth size of inner; toes slender, bearing lateral fringes and discs (about as wide as long) on expanded pads; webbing absent; relative lengths of toes I <II <III <V <IV; toe III much shorter than toe V; toe III extending to distal edge of the antepenultimate subarticular tubercle on toe IV; toe V extending to edge distal of the penultimate subarticular tubercle on toe IV; all toes having terminal ventral pads well defined by circumferential grooves; discs of toes III–V equal to discs on fingers II–IV and larger than discs of toe I; subarticular tubercles round, prominent, two on toes I and II, three on toes III and V, and four on toe IV; supernumerary plantar tubercles low, rounded, numerous on proximal segments of digits.

Measurements of holotype (mm). —SVL 28.0, tibia length 14.0, foot length 14.0, HL 9.0, head width 11.0, IOD 4.0, internarial distance 2.0, width of upper eyelid 2.0, diameter of eye 3.0, eye–nostril distance 2.0.

Distribution. — Pristimantis sneiderni is known only from the type locality, the vicinity the Laguna de San Rafael, Páramo de Puracé, Cauca, Colombia ( Fig. 4 ). The Laguna de San Rafael is located within the Puracé National Park, Cordillera Central, Colombia.

Etymology. —The specific name is a noun in the genitive case and is a patronym for the naturalist, taxidermist, and collector Kjell von Sneidern (1910–1999), who first found the species during his explorations of Puracé, Cauca. Originally from Sweden, von Sneidern was director of the Museo de Historia Natural de la Universidad del Cauca from 1940–1960, and founder in 1954 of NoƲedades Colombianas, the journal published by the Museo de Historia Natural de la Universidad del Cauca.

Remarks. —Kjell von Sneidern visited the Laguna de San Rafael (southeast of Popayán) at the end of 1938 and the beginning of 1939. Together with the new species, von Sneidern collected Atelopus ebenoides Rivero 1963 , Osornophrŋne bufoniformis ( Peracca 1904) , Hŋloxalus pinguis (Rivero and Granado-Díaz 1990) , Pristimantis buckleŋi ( Boulenger 1882) , and P. obmutescens ( Lynch 1980b) . WED (with L. Trueb and J.E. Simmons) in September 1974 visited several sites in Puracé, vicinity of the type locality. They found two species of bufonids ( A. ebenoides and O. bufoniformis ) and six species of Pristimantis — P. boulengeri , P. buckleŋi , P. leptolophus ( Lynch 1980b) , P. mŋersi ( Goin and Cochran 1963) , P. obmutescens , and P. Ʋicarius ( Lynch and Ruiz-Carranza 1983) .

Figures

FIG. 5.—Dorsolateral, ventral, and lateral views of Pristimantis sneiderni (A, B; holotype, KU 145021, adult female, snout–vent length [SVL] 28 mm, head length [HL] 9.0 mm), P. boulengeri (C, D; paratype, KU 169062, adult female, SVL 34 mm, HL 10.6 mm), and P. schultei (E, F; paratype, KU 209504, adult female, SVL 33 mm, HL 10.5 mm). A color version of this figure is available online.

FIG. 6.—Dorsolateral and ventral views of the male of Pristimantis sneiderni (A, B; paratype, KU 145019, adult male, snout–vent length [SVL] 23 mm) and P. deŋi (C, D; holotype, MUSM 8968, adult male, SVL 22.7 mm; photo Magnolia Press, reproduced with permission from copyright holder). A color version of this figure is available online.

FIG. 4.—Map of southwestern Colombia (inset) showing the type localities of Pristimantis calima (star) and P. sneiderni (triangle). Lines indicate boundaries of the two departments within which the new species are known to occur.