Researchers from Peru have discovered a new colorful lizard which they named Potamites montanicola, or “mountain dweller”.
The new species was found in Cordillera de Vilcabamba and Apurimac river valley, the Cusco Region of Peru at altitude ranging from 1,600 to 2,100 meters. Their study was published in the open access journal ZooKeys.
“The new discovery raises some questions”, say the authors. This is the only member of the genus known to live at such altitude. It is yet unknown what biological mechanisms help the lizard to survive in this harsh environment, much colder than what it’s relatives in the genus prefer.
Scientists also believe the lizard may be nocturnal, which raises the question of how it maintains its body temperature during night time. In some cases, individuals were observed swimming in streams, which is rather unusual behavior for the members this genus.
“Further studies are needed to reveal its biology, population structure and conservation status, and outline its overall distribution”, Chávez concludes.
The semi aquatic lizards of the genus Potamites were considered as Neusticurus for many years, this genus included eleven species, however Neusticurus is currently represented only by five species and the other six are included in the genus Potamites (Doan and Castoe 2005).
Two species of Potamites occur formerly in Peru: Potamites ecpleopus and Potamites strangulatus; Potamites strangulatus has two recognized subspecies: Potamites strangulatus strangulatus and Potamites strangulatus trachodus, recorded in the Amazonian lowlands between 100 and 800 m elevations in the centre and the north respectively (Uzell 1966) and easily distinguishable by the absence or presence of tubercles on the flanks.
Additionally another species of the genus, Potamites juruazenzis, was described from rio Juruá, Acre state, at southwestern Brazil (Avila-Pires and Vitt 1998), but even though it has never been recorded in Peru, its occurrence there is expected due to the proximity of the type locality to the borderline with the Ucayali Region. Potamites ocellatus (Sinitsin 1930) was described with a holotype from Rurrenabaque (Beni region, Bolivia) and 54 paratypes from Chanchamayo and Perené valleys (Junin, Peru).
However, the variation in the paratypes was not included in the description, and given the distance between both sites (approximately 1000 km airline), they were questioned to belong to the same species. Sinitsin in a footnote explains that the new form would be analized by Charles E. Burt in another paper. In the new publication, Burt and Burt (1931) conclude that Potamites ocellatus is a subspecies of Potamites ecpleopus because the scutellation and measurements are similar to Potamites ecpleopus.
Some years later, Uzell (1966) proposed the subspecies Potamites ecpleopus ocellatus to be a synonym of Potamites ecpleopus and later on Vanzolini (1995) resurrected Potamites ocellatus and elevated it to the species level (but in reference to the Bolivian holotype only). Even though, the genus Potamites still presents several taxonomic uncertainties, it also proves that its diversity is also underestimated and poorly studied.
Recent surveys carried out during 2010 gave as a result the discovery of a new species of Potamites from southern Peru, which is described herein.