Saturday, July 16, 2016

[Herpetology • 2012] Eupsophus altor • A New Species of Eupsophus (Amphibia: Neobatrachia) from the Valdivian Coastal Range, Southern Chile: An Integrative Taxonomic Approach

Eupsophus altor  
Nuñez, Rabanal & Formas, 2012 

We describe a new species of Eupsophus from the Coastal Range of Southern Chile. The new taxon can be differentiated using an integrative taxonomic approach that includes advertisement call, reproductive mode, tadpoles, and mtDNA D-loop sequences. Based on karyological characters, the new species is assigned to the roseus Group (2N=30), and differs from all described species therein by having early winter breeding season, terrestrial tadpoles and its advertisement call with spectral elements reaching the 20 kHz. Phylogenetic analyses based on mitochondrial data place the new species as sister taxon of Emigueli. The discovery of this new species highlights the importance of the multisource approaches to discover cryptic diversity as well as to establish the basis for prioritizing policies and conservation efforts on Chilean batrachofauna.

Key words: Amphibia, Neobatrachia, Eupsophus altor sp. nov., integrative taxonomy, Chile

FIGURE 5. A. Holotype of Eupsophus altor sp. nov. (IZUA 3607) from Cerro Oncol (Valdivia Province). B: Terrestrial embryos of Eupsophus altor sp. nov. C: Nest with tadpoles of Eupsophus altor sp. nov. Stage 30. D: Tadpoles at stages 37–41.
Stages according to Gosner (1960). Bar indicates 10 mm. 

Eupsophus altor sp. nov. Nuñez, Rabanal & Formas 
Oncol’s ground frog (English) Rana de hojarasca de Oncol (Spanish)

Diagnosis. The species is assigned to the genus Eupsophus because it has the following osteological cranial pattern (cervical cotylar arrangement type II; palatal shelf of premaxilla relatively deep; palatal shelf of maxilla of moderate width; pterygoid process moderately large; nasals small, widely separated medially; nasals in broad contact with maxillae, not in contact with pterygoids; epiotic eminences prominent; zygomatic ramus of squamosal of moderate length, widely separated from maxilla; otic ramus of squamosal as long as zygomatic ramus, expanded medially into small otic plate; squamosal-maxillary angle 50–55°; palatines broad, widely separated medially, bearing odontoid ridges; sphenethmoid entire, extending anteriorly to anterior edge of nasals parasphenoid alae oriented at right angles to anterior ramus of parasphenoid, broadly overlapped laterally by median rami of pterygoid) as has been described by Lynch (1971) and endotrophic tadpoles (Formas 1985). Eupsophus altor is assigned to the E. roseus Group species by having 2n = 30 chromosomes. Eupsophus altor differs from all species described of the E. roseus group species by having early winter breeding season, terrestrial tadpoles and its advertisement call with spectral elements reaching the 20 kHz, and nine mitochondrial D-loop nucleotide site substitutions from its congeneric species phylogenetically closest.

Distribution and natural history. At present, specimens of Eupsophus altor are known from the type locality and three additional sites [Alepue (39º36’S; 73º14’W), Chan-Chán (39º33’S; 73º12’W) and Curiñanco (39º39’S; 73º18’W)] located the western slopes of the Coastal range, between the mouth of the rivers Lingue (39º26’S; 73º12’W) and Valdivia (39º52’S; 73º23’W), Valdivia province. This area is covered by the typical vegetation of Valdivian rain forest (Veblen 2007) where the following plants were identified: Drymis winteri, Laurelia phyllipiana, Weinmannia trichosperma, Dendroligotrichum dendroides, and Cladonia spp. There, the most common frogs are: Alsodes norae, Batrachyla antartandica, Batrachyla leptopus, Eupsophus vertebralis, Pleurodema thaul, and Rhinoderma darwinii. During January and February (austral summer) specimens of the small lizards Liolaemus pictus and L. cyanogaster were observed. Throughout the year, adult specimens of E. altor were found under rotten trees and at night walking through the vegetation ground. Mating calls (maximum activity at night), males with nuptial pads and gravid females were observed throughout May and August (austral winter). The clutches and tadpoles were always observed during May and June, and tadpoles between May and October in terrestrial nests, under logs or tree holes until 1 m above the ground (Fig 5B, C, D). 

Etymology. The specific name altor is derived from the Latin meaning “one who looks after or brings up its offspring”. This epithet is given in the masculine form of the word (the female form is altex) because we observed that in this species males are the care givers for offspring. 

José J Nuñez, Felipe E Rabanal and J. Ramon Formas. 2012. Description of A New Species of Eupsophus (Amphibia: Neobatrachia) from the Valdivian Coastal Range, Southern Chile: An Integrative Taxonomic Approach.  Zootaxa. 3305; 53- 68.