Monday, January 11, 2021

[Herpetology • 2020] Rhinella exostosica • A New Species of Leaf-litter Toad of the Rhinella margaritifera Species Group (Anura: Bufonidae) from Amazonia


Rhinella exostosica 
Ferrão, Lima, Ron, dos Santos & Hanken, 2020

Photographs by Albertina P. Lima.

Abstract
We describe through integrative taxonomy a new Amazonian species of leaf-litter toad of the Rhinella margaritifera species group. The new species inhabits open lowland forest in southwest Amazonia in Brazil, Peru, and Bolivia. It is closely related to a Bolivian species tentatively identified as Rhinella cf. paraguayensis. Both the new species and R. paraguayensis share an uncommon breeding strategy among their Amazonian congeners: each breeds in moderate to large rivers instead of small streams or ponds formed by rainwater. The new species is easily differentiated from other members of the R. margaritifera species group by having a strongly developed bony protrusion at the angle of the jaw, a snout–vent length of 63.4–84.7 mm in females and 56.3–72.3 mm in males, well-developed supratympanic crests with the proximal portion shorter than the parotoid gland in lateral view, a divided distal subarticular tubercle on finger III, and multinoted calls composed of groups of 7–9 pulsed notes and a dominant frequency of 1,012–1,163 Hz. Recent studies have shown that the upper Madeira Basin harbors a megadiverse fauna of anurans, including several candidate species. This is the first member of the R. margaritifera species group to be described from this region in recent years, and at least two additional unnamed species await formal description.


Adult female paratopotype of Rhinella exostosica, new species [INPAH 41322]
from Jací Direito Sampling Module, the upper Madeira River, municipality of Porto Velho, Rondônia, Brazil.
 Photographs by Albertina P. Lima.
 
Coloration in life of the adult male holotype of Rhinella exostosica, new species, INPAH 41323 (field number APL 19973). 
Photographs by Albertina P. Lima.

Rhinella exostosica, new species

Etymology.— The specific epithet exostosica is derived from the Latin ‘‘exostosis’’ and a reference to the strongly developed bony protrusion at the angle of the jaw of the new species. 


Miquéias Ferrão, Albertina Pimentel Lima, Santiago Ron, Sueny Paloma dos Santos and James Hanken. 2020. New Species of Leaf-litter Toad of the Rhinella margaritifera Species Group (Anura: Bufonidae) from Amazonia. Copeia. 108(4); 967-986 . DOI: 10.1643/CH2020043