Thursday, June 25, 2020

[Herpetology • 2020] Phrynopus remotum • A New Species of Frog (Terrarana, Strabomantidae) from the Peruvian Andean Grasslands

Phrynopus remotum  
Chávez​, García Ayachi & Catenazzi, 2020

We describe a new, medium-sized species of terrestrial frog of the genus Phrynopus from a single locality in the central Andes of Peru (Departamento de Huánuco) at 3,730 meters of elevation. Phylogenetic analyses supported Phrynopus remotum sp. nov. as an independent lineage, sister to most of its congeners. The new species is morphologically distinguishable by the presence of small tubercles on upper eyelids and heels, an areolate venter, and the absence of dorsolateral folds or ridges. This species inhabits the highlands adjacent to the Marañón Dry valley. The only sympatric amphibian species recorded is the marsupial frog Gastrotheca peruana.

Figure 3: Holotype of Phrynopus remotum sp nov. in life.
Dorsal and ventral view of the holotype in life (CORBIDI 20533, SVL =28.7 mm). 

Figure 5: Paratypes of Phrynopus remotum sp nov. in life.
 Dorsal (left column) and ventral (right column) views of the paratypes:
(A–B) CORBIDI 20531 (SVL =23.3 mm); (C–D) CORBIDI 20532 (SVL =19.3 mm).

Phrynopus remotum sp. nov.

Diagnosis: A species of Phrynopus having the following combination of characters: (1) Skin on dorsum shagreened with scattered low subconical tubercles, skin on venter areolate; discoidal fold absent, thoracic fold absent; postocular fold absent, dorsolateral folds absent; (2) tympanic membrane and tympanic annulus absent; (3) snout short, rounded in dorsal view, curved anteroventrally from lateral view; (4) upper eyelid with small rounded tubercles; width of upper eyelid 1.9–2 mm; (5) dentigerous process of vomers present, oblique; (6) vocal slits and nuptial pads absent; (7) Finger I slightly shorter than Finger II; tips of digit bulbous, rounded, lacking discs; (8) fingers without lateral fringes; (9) ulnar and tarsal tubercles absent; (10) heels with one or two small rounded tubercles, inner tarsal fold absent; (11) inner metatarsal tubercle rounded, about 1.3 times as large as ovoid outer metatarsal tubercle; supernumerary plantar tubercles absent; (12) toes without lateral fringes, basal webbing absent, Toe V slightly shorter than Toe III, toe tips bulbous, lacking discs; (13) in life, dorsum saffron yellow, brownish-orange or dark brown with dark brown or black blotches, dark spots on flanks; throat, chest and venter yellowish-white with dark brown blotches or spots, groin grayish-white with liver brown or dark brown spots and blotches; iris olive gray with fine dark brown reticulations; (14) SVL 19.3 and 23.3 mm in two males, and 28.7 mm in a single female.

Etymology. The specific name remotum is the neutral form derived from the Latin word “remotus”, in reference to the long journey required to reach the type locality of this species. This journey consisted of more than 30 h traveling through roadways, hiking trails and steep slopes of rocky mountains. 

Figure 6: Habitat of Phrynopus remotum sp nov. in the Puna grasslands of the central Pruvian Andes (Huánuco Department).

Distribution, natural history, and conservation status. This species is known only from the type locality at 3,700 m a.s.l. in the eastern Andean slopes of Central Peru (Fig. 1). The habitat is a transitional area between wet grasslands and some remaining patches of cloud forest and bushes. We found all specimens around 12:30 pm under stones surrounded by moss and lichens, alongside a temporary stream bordering a wet grassland. The only sympatric amphibian found was Gastrotheca peruana, which was frequently spotted under stones and also beneath the moss; however none of these frogs were found sharing a stone with P. remotum sp. nov. We noticed heavy presence of livestock (Fig. 6). Local people annually burn the grassland to trigger regrowth of grass plants (Festuca, Stipa spp.) and to open new pasture grounds for cattle. Despite these threats (Catenazzi & von May, 2014), the paucity of data on the geographic distribution of this species prevents assessment of its threat status. Therefore, we recommend the Category Data Deficient for the IUCN Red List. Future surveys should document the range of the species and assess the importance of threats.

Germán Chávez​, Luis Alberto García Ayachi and Alessandro Catenazzi. 2020. A New Species of Frog (Terrarana, Strabomantidae, Phrynopus) from the Peruvian Andean Grasslands. PeerJ. 8:e9433. DOI: 10.7717/peerj.9433