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| Osteocephalus vasquezi Venegas, García-Ayachi, Toral, Malqui & Ron, 2023 |
Abstract
We describe a new species of Osteocephalus Fitzinger, 1843 using morphological traits of adult frogs and its larvae, as well as molecular evidence. The new species occurs in the premontane forest of the Cordillera del Yanachaga in the Andes of central Peru, at elevations between 1000 and 1150 m a.s.l. It belongs to the Osteocephalus mimeticus species group and is the sister species of O. mimeticus. It is most similar to three species with predominantly dark irises, tuberculate dorsal skin, and brown dorsal coloration: O. festae Peracca, 1904, O. mimeticus Melin, 1941, and O. verruciger Werner, 1901. Of these three species, the most similar is O. mimeticus. However, the new species can be easily distinguished from O. mimeticus by having a cream or creamy-tan venter with a well-defined pattern of brown chocolate blotches and flecks (venter cream, tan, or brown without marks in O. mimeticus). The tadpoles of O. vasquezi sp. nov. are strikingly different from the tadpoles of O. mimeticus by having a larger oral disk with nine lower labial tooth rows (only six in O. mimeticus). Tadpoles of the new species and those of O. festae are unique among Osteocephalus by belonging to the suctorial ecomorphological guild as shown by their large oral disks. Our time tree suggest that the new species diverged from its sister species at the beginning of the Pleistocene, ~2.5 million years ago.
Key Words: Biodiversity, DNA, new species, Osteocephalus mimeticus, phylogeny, tadpole, taxonomy
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| Dorsolateral and ventral views of Osteocephalus vasquezi sp. nov. A, B. Dorsolateral and ventral view of holotype CORBIDI 7284, SVL = 51.4 mm; C, D. Dorsolateral and ventral view of adult male, CORBIDI 7285, SVL = 40.8 mm; E, F. Dorsolateral and ventral view of adult female CORBIDI 7280, SVL = 65.9 mm; G. Dorsolateral view of a recently metamorphosed CORBIDI 7304, SVL = 13 mm; H. Dorsolateral view of tadpole in stage 42. Photographs by P.J. Venegas. |
Osteocephalus vasquezi sp. nov.
Definition: Osteocephalus vasquezi sp. nov. can be distinguished from its congeners by the following combination of characters: (1) size sexually dimorphic; maximum SVL in males 52.9 mm (n = 14), in females 75.5 mm (n = 2); (2) skin on dorsum of breeding males bearing conical tubercles with keratinized tips, not present in non-breeding males, smooth in females; (3) skin on flanks weakly areolate in the anterior two-thirds and smooth posteriorly; (4) hand webbing formula varies from II2–—3–III2½—2+IV to I basal II2––—3+III3—2½IV; foot webbing formula varies from I1–—1II1–—1–III0—1–IV1–—1–V to I1—2–II1—2–III2–—2–IV2––—1V; (5) in life, dorsum varies from brown to dark brown or orange-brown, with or without dark brown irregular marks; (6) throat brown or tan with a distinctive pattern of white irregular blotches or vermiculations, as well as tan to brown blotches on a whitish cream to creamy tan background; chest and belly cream or creamy tan with chocolate blotches or flecks; (7) cream suborbital mark indistinct, clear labial stripe distinct or faint; (8) color of dorsolateral region of flanks similar to dorsal coloration; ventrolateral region whitish cream or brownish cream with brown scattered blotches and/or vermiculations; (9) dermal roofing bones of the skull not exposed; (10) in life, bones green; (11) in life, iris dark brown with golden vermiculations or flecks; (12) vocal sacs paired, small, located laterally, behind jaw articulation; (13) in life, juveniles with red iris, dorsal surface of body and limbs dark brown (almost black) with marks or coppery with dark brown marks, without conspicuous pale elbows, knees, and heels; (14) larvae with LTRF of 3/9.
Etymology: The specific name is a patronym for Pedro Vásquez Ruesta, a Peruvian forest engineer, who is a pioneer in the wildlife management in Peru. Since 1978 he has worked for the development of wildlife management and protected natural areas as a professor at the Faculty of Forestry at Universidad Nacional Agraria La Molina, Lima, Peru, teaching to generations of forest engineers about wildlife management and conservation. During his academic life, Pedro Vásquez Ruesta made many contributions to the field of conservation of natural resources, advising theses and published scientific articles especially about the management of caimans and deer.
Pablo J. Venegas, Luis A. García-Ayachi, Eduardo Toral, José Malqui and Santiago R. Ron. 2023. A New Species of Spiny-backed Tree Frog, Genus Osteocephalus (Anura, Hylidae), from the Yanachaga Chemillén National Park in central Peru. Evolutionary Systematics. 7(2): 237-251. DOI: 10.3897/evolsyst.7.102360
