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| Pristimantis asimus Köhler, Glaw, Aguilar-Puntriano, Castroviejo-Fisher, Chaparro, De la Riva, Gagliardi-Urrutia, Gutiérrez, Vences & Padial, 2024 |
Abstract
We describe a new frog species that is the sibling of Pristimantis reichlei. These two sister species inhabit the Amazonian lowlands and adjacent foothills of the Andes, from central Bolivia to central Peru. Pristimantis reichlei occurs from central Bolivia to southern Peru (Alto Purús National Park), while the new species occurs from northern Bolivia (Departamento Pando) to Panguana in central Peru (Departamento Huánuco), at elevations between 220 and 470 m a.s.l. In spite of their morphological crypsis, these siblings occur in syntopy without evidence of interbreeding (in the Alto Purús area) and are recovered as reciprocally monophyletic. Their uncorrected pairwise genetic distances in the 16S rRNA gene range from 9.5–13.5%, and their advertisement calls differ in both qualitative and quantitative traits. Moreover, our study found uncorrected pairwise distances within the new species of up to 5.0% and up to 9.3% within P. reichlei. We therefore cannot rule out the possible existence of hybrids or additional species-level lineages hidden in this complex. Furthermore, we found another potential pair of sibling species composed of P. danae and an unnamed lineage, with divergences of 9.4% in the 16S gene, whose in-depth analysis and taxonomic treatment are pending future revision. With the new nominal species, the Pristimantis danae species group now includes 20 species, distributed across the upper Amazon basin and in the eastern Andes, from western Brazil to Bolivia and Peru. Our study, together with an increasing number of other studies, indicates that sibling species are far from being rare among Amazonian amphibians and that species resolution remains low even for groups that have received considerable attention in recent years.
Key Words: Amphibia, bioacoustics, integrative taxonomy, morphology, molecular genetics, systematics, Bolivia, Brazil, Peru
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| Male holotype of Pristimantis asimus sp. nov. (MUSM 41241, FGZC 5342) from Panguana, Departamento Huánuco, Peru, in life (SVL 30.6 mm): a. Dorsolateral view; b. Dorsal view (showing posterior thighs coloration); c. Ventral view. |
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| Paratypes of Pristimantis asimus sp. nov. in life (dorsolateral and ventral views): a. ZSM 1985/2008 (FGZC 3388; SVL 30.6 mm); b. ZSM 1986/2008 (FGZC 3389; SVL 28.4 mm); c. MUSM 29074 (FGZC 3273; SVL 28.3 mm), all from the type locality Panguana, Huánuco, Peru; d. CM 158600, from Río Sepahua, Ucayali, Peru. |
Pristimantis asimus sp. nov.
Definition: A medium-sized species of the Pristimantis danae species group (based on molecular relationships and morphological similarity), with 27.7‒30.6 mm SVL in adult males (n = 7), and 37.9 mm SVL in adult females (n = 1), characterized by: (1) skin on dorsum finely shagreened, lacking enlarged tubercles or warts; throat smooth, venter areolate; discoidal fold inconspicuous; dorsolateral folds absent; upper eyelid lacking tubercles and granules; posterior surfaces of thighs smooth; (2) tympanic membrane and annulus distinct, slightly higher than long, their length less than half of eye diameter; supratympanic fold prominent, curved, slightly covering upper edge of tympanic annulus; (3) head slightly longer than wide; snout subacuminate in dorsal view, bluntly rounded in lateral profile; canthus rostralis straight in dorsal view, slightly ...
Etymology: The specific epithet is a Latinized adjective derived from the Greek άσημος (ásimos), meaning ‘inconspicuous, nameless’. It refers to the morphologically cryptic nature of the new species and the fact that it has been associated with different species names in the past, missing its status as a separate species to be named.
Jörn Köhler, Frank Glaw, César Aguilar-Puntriano, Santiago Castroviejo-Fisher, Juan C. Chaparro, Ignacio De la Riva, Giussepe Gagliardi-Urrutia, Roberto Gutiérrez, Miguel Vences and José M. Padial. 2024. Similar looking Sisters: A New sibling Species in the Pristimantis danae group from the southwestern Amazon Basin (Anura, Strabomantidae). Zoosystematics and Evolution. 100(2): 565-582. DOI: 10.3897/zse.100.119143
