Cryptobatrachus ruthveni, Lynch, John D., 2008

Lynch, John D., 2008, A taxonomic revision of frogs of the genus Cryptobatrachus (Anura: Hemiphractidae), Zootaxa 1883, pp. 28-68 : 63

Cryptobatrachus ruthveni sp. nov.

Holotype: ICN 7147, an adult male, one of a series collected at Montañita, San Pedro de la Sierra, municipio de Ciénaga, Magdalena, Colombia, 1400 m, by M. Cristina Ardila , in January 1981.

Paratypes: ICN 3085, 7145, 7146, 7148, 7151-52 (from the type-locality), 35257, 35260 from Hacienda Guandosaca, 1540 m.

Diagnosis: A Cryptobatrachus with thin dorsolateral folds, finely granular skin on the dorsum with scattered larger warts ( Fig. 10 B), fingers lacking webbing, with subarticular adhesive pads, expanded disks on the digits, exhibiting sexual dimorphism in the size of the tympanum, and not having the anterior part of the braincase broader than the middle part.

Externally, C. ruthveni is nearly indistinguishable from C. boulengeri . In C. boulengeri , the enlarged tubercles on the dorsum are restricted to the shoulders whereas in C. ruthveni , these occur over nearly all parts of the dorsum. An osteological difference (failure of the anterior part of the braincase to expand laterally during ontogeny) serves to distinguish the two species.

Etymology. Named for Alexander G. Ruthven who first recognized the novelty and relationships of one of the frog species that he named from the Sierra Nevada de Santa Marta.

Description: Head width greater than head length, broader than body in males and juveniles, narrower than body in adult females; snout subacuminate in dorsal view, rounded in profile; nostrils protuberant, directed dorsolaterally; canthus rostralis sharp, weakly concave; loreal region concave; lips not flared; skin of upper eyelid finely granular except for one or two larger warts on posterior part; interorbital space flat (no cranial crests); temporal region sloping abruptly to lip; tympanum round; supratympanic fold prominent, posterior to tympanum interrupted as series of elongate warts; postrictal tubercles rounded; choanae rounded, not concealed by platal shelf of maxillary arch; dentigerous processes of vomers posterior to choanae, not in median contact, bearing straight row of 10-13 teeth; tongue longer than wide, its posterior border bearing shallow notch or not, completely adherent to floor of mouth; adult males lacking vocal slits or vocal sac.

Skin of dorsum finely granular but with a scattering of larger warts except for most of upper eyelids and snout; dorsolateral folds represented by series of elongate tubercles extending from just posterior to supratympanic fold to level of sacrum (or just beyond); skin of venter coarsely granular.

Thenar tubercle oval, much larger than oval palmar tubercle; no supernumerary palmar tubercles; basal subarticular tubercles round, distal subarticular tubercles broader than long, bearing adhesive pads defined by complete circumferential grooves; fingers bearing ventrolateral keels; discs of I and II round, those of III and IV broader than long; first finger longer than second.

No tubercles on heel or inner edge of tarsus; outer edge of tarsus bearing series of very low, small tubercles; inner metatarsal tubercle 2 ½ times as long as wide; outer metatarsal tubercle very small (about 1/5 size of inner), not prominent; no supernumerary plantar tubercles; lateral fringe along medial surface of Toe I; fleshy keel along lateral surface of Toe V; basal subarticular tubercles of Toes IV-V small, other subarticular tubercles larger; distal subarticular tubercles of all five toes (and penultimate subarticular tubercle of Toe IV) bearing circumferential groves partially defining adhesive pads; groves on tubercles of Toes I-II complete proximally and laterally, on other subarticular tubercles, complete laterally, proximally, and medially (Ushaped); discs of toes round; heels of flexed hindlimbs, held perpendicular to sagittal plane, overlapping.

Coloration in alcohol: dorsum brown with pale brown blotches; limbs pale brown with darker brown bands; posterior surfaces of thighs reticulated with dark brown, defining cream spots; throat and anterior venter spotted with brown; flanks brown with cream spots; undersides of limbs cream.

Measurements of holotype in mm.: SVL 43.9, shank 25.5, head width 17.5, upper eyelid width 4.8, IOD 3.2, tympanum length 3.3, eye length 7.2, E-N 4.4.

Distribution: This species is known from the immediate vicinity of San Pedro de la Sierra, on the western flank of the Sierra Nevada de Santa Marta, between 1400 and 1540 m.

Figures

FIGURE 10. Skin texture (distribution of enlarged tubercles and folds) of Cryptobatrachus. (A) C. pedroruizi (ICN 38720) and (B) C. ruthveni (ICN 7151). Scale equals 2 mm.