Monday, November 15, 2021

[Herpetology • 2019] Cyrtodactylus muluensis & C. limajalur Uncovering Karst Endemism within Borneo: Two New Cyrtodactylus Species (Squamata: Gekkonidae) from Sarawak, Malaysia


Cyrtodactylus muluensis 
Davis, Bauer. Jackman, Nashriq & Das, 2019


Abstract
The island of Borneo lies within one of the most biodiverse regions in the world. Despite this, its documented gekkonid diversity is not commensurate with other areas of Southeast Asia. The megadiverse genus Cyrtodactylus is especially underrepresented. Limestone-karst ecosystems, in particular, harbor many endemic Cyrtodactylus species, but only one karst-dwelling species is currently recognized from Borneo. This paper adds two additional karst-dwelling Cyrtodactylus species—C. muluensis sp. nov. and C. limajalur sp. nov.—from Sarawak, Malaysia. Cyrtodactylus muluensis sp. nov. is endemic to Gunung Mulu and is distinguished from its congeners by having a precloacal groove, 31–38 ventral scales, a maximum SVL of at least 88 mm, enlarged subcaudals, 19–20 subdigital lamellae, and a banded dorsal body pattern. Cyrtodactylus limajalur sp. nov. is endemic to the Serian region and is distinguished from its congeners by having 33–42 ventral scales, enlarged subcaudals, a precloacal pit, a maximum SVL of at least 94 mm, 5–6 enlarged femoral scales, 19–22 subdigital lamellae, and five distinct bands on the dorsum. Both species are phylogenetically distinct and deeply divergent from all other congeners. The description of two new karst-dwelling species highlights the need to conserve karst habitats and the endemic species they harbor.

Keywords: Gekkonidae, squamate, biodiversity, limestone, karst, Borneo, Reptilia


Photograph of live paratype of Cyrtodactylus limajalur sp. nov. (CAS 262846).

Cyrtodactylus limajalur sp. nov. 
Five-banded Bent-toed Gecko

Etymology. The specific epithet limajalur is in reference to the banding pattern of the species. “Lima jalur” loosely translated from Malay is five-bandedCyrtodactylus limajalur sp. nov. has a very distinct banding pattern that is consistently comprised of five bands. This species is the first Bornean Cyrtodactylus species that displays a consistent banding pattern, without blotches or other markings.


Photographs of live individuals of Cyrtodactylus muluensis sp. nov. 
A) adult holotype (CAS 262983);  B) juvenile paratype (CAS 262995).

Cyrtodactylus muluensis sp. nov. 
Mulu Bent-Toed Gecko 

Distribution. Cyrtodactylus muluensis sp. nov. is known from the Clearwater Cave, Long Cave, and Lang Cave within Mulu National Park, Sarawak, East Malaysia. The Clearwater Cave and Long Cave are on the same karst peak ~1 km apart. The Mulu area has a high concentration of limestone karst formations, most of which were not surveyed over the course of our work (Fig. 3). 

Etymology. The specific epithet muluensis is in reference to the type locality, Gunung Mulu National Park. As this is the first endemic gekkonid described from Gunung Mulu, the name muluensis is fitting.
 

Hayden R. Davis, Aaron M. Bauer. Todd R. Jackman, Izneil Nashriq and Indraneil Das. 2019. Uncovering Karst Endemism within Borneo: Two New Cyrtodactylus Species from Sarawak, Malaysia. Zootaxa. 4614(2); 331–352. DOI: 10.11646/zootaxa.4614.2.4