Sunday, February 7, 2016

[Herpetology • 2011] Cyrtodactylus boreoclivus • A New Species of Bent-toed Gecko (Cyrtodactylus, Gekkonidae) from the Torricelli and Foja Mountain ranges of northern New Guinea

Cyrtodactylus boreoclivus
Oliver, Krey, Mumpuni & Richards, 2011

FIGURE 4. Paratypes [SJR13613] of Cyrtodactylus boreoclivus sp. nov. from the Foja Mountains.
 Photograph: T. Laman and National Geographic. 


We describe a new species of Cyrtodactylus from lower montane forests on the Torricelli and Foja Mountain ranges of northern New Guinea. Cyrtodactylus boreoclivus sp. nov. can be distinguished from all other described Cyrtodactylus by the combination of moderately large size (SVL 104–109 mm), males with pores extending to the knee and arranged in independent precloacal and femoral series, transversely enlarged subcaudal scales, and dorsal pattern consisting of five to seven indistinct transverse dark bands. The known distribution of this species is similar to many other vertebrate taxa apparently restricted to isolated ranges within the North Papuan Mountains, and supports the biogeographic association of these poorly known upland areas.

Keywords: Foja Mountains; Indonesia; Papua New Guinea; Torricelli Mountains

Etymology. From  the  latin  boreo-  meaning  northern,  and  -clivus  meaning  slopes,  in  reference  to  the  northern Ranges of New Guinea, to which the species is presumably endemic.

Despite a spate of recent descriptions (Rösler 2000, Günther and Rösler 2003, Kraus and Allison 2006a, Rösler et al. 2007, Oliver et al. 2008, 2009, Kraus 2007, 2008), many additional Crytodactylus from New Guinea remain undescribed. Based on existing museum collections and unpublished genetic data it seems that actual diversity maybe as high as double the currently recognised total (Oliver pers. obs., Kraus pers. com.). Many described species also remain known from either few specimens and/or only one or two localities. Given this abundance of unrecognised and/or poorly known taxa, and pending the results of genetic investigations currently underway (Oliver unpublished), we do not speculate about the evolutionary relationships of Cyrtodactylus boreoclivus sp. nov.

Cyrtodactylus boreoclivus

FIGURE 4. Paratypes [SJR13613] of Cyrtodactylus boreoclivus sp. nov. from the Foja Mountains.
Photograph: T. Laman and National Geographic. 
The northern lowlands of New Guinea have been the focus of several recent herpetofaunal surveys but Cyrtodactylus boreoclivus sp. nov. has not been found during these projects (e.g., Austin et al. 2008, SJR pers. obs., Fred Kraus pers. com.). Furthermore, while Cyrtodactylus boreoclivus sp. nov. was moderately common in the Foja mountains at 1200 metres, extensive survey work at lower altitudes in the Fojas documented only C. novaeguineae and C. mimikanus. It seems likely that the new species is restricted to moderately high altitudes within the North Papuan Mountains. This is the second species of Melanesian Cyrtodactylus known only from altitudes of 1000 metres and above (the other being C. capreoloides from the Central cordillera (Rösler et al. 2007)). Given the topographic complexity of New Guinea, and the influence of altitude on species diversity patterns in other elements of the New Guinea fauna, we suspect that additional work will reveal further upland endemic Cyrtodactylus elsewhere in New Guinea, especially within the large areas of lower montane forest along the Central Cordillera.

 Based on its known distribution, Cyrtodactylus boreoclivus sp. nov. is one of a growing suite of species that occur in two or more apparently isolated montane populations in disparate North Papuan Mountain Ranges (Helgen 2007; Kraus and Allison 2006b). Further morphological and genetic work will almost certainly reveal many more species, or sister-species complexes, that are restricted to montane isolates within these ranges. Given that many of these montane taxa endemic to the North Papuan Mountains are poor dispersers and unlikely to have been extirpated by recent anthropogenic influences, their current distribution indicates that there was historical connectivity and gene flow between these now-isolated montane blocks. While modern assessments of biogeographical history are in their infancy in New Guinea, a genetic assessment of diversity within taxa distributed across the North Papuan Mountains would provide a valuable insight into the temporal scale and historical processes responsible for this distribution pattern.

Paul Oliver, Keliopas Krey, Mumpuni and Stephen Richards. 2011. A New Species of Bent-toed Gecko (Cyrtodactylus, Gekkonidae) from the North Papuan Mountains. Zootaxa. 2930: 22–32

New Bent-Toed Gecko Found in "Lost World"