Sunday, October 30, 2016

[Herpetology • 2016] Sphenomorphus sungaicolus • The First Riparian Skink (Genus: Sphenomorphus Strauch, 1887) from Peninsular Malaysia and Its Relationship to other Indochinese and Sundaic Species


Sphenomorphus sungaicolus 
Sumarli, Grismer, Wood, Ahmad, Rizal, Ismail, Izam, Ahmad & Linkem, 2016

(A) Holotype of Sphenomorphus sungaicolus sp. nov. (LSUHC 11722) from Hutan Lipur Sekayu, Terengganu, Peninsular Malaysia. . Photograph by L. Grismer.
(B) Juvenile S. sungaicolus sp. nov. (not collected) from the Korbu Forest Reserve, Perak. Photograph by Z. Dzulkafly.  flickr.com 

Abstract

Recently discovered populations of skinks of the genus Sphenomorphus from central Peninsular Malaysia represent a new species, Sphenomorphus sungaicolus sp. nov., and the first riparian skink known from Peninsular Malaysia. Morphological analyses of an earlier specimen reported as S. tersus from the Forest Research Institute of Malaysia (FRIM), Selangor indicate that it too is the new riparian species S. sungaicolus sp. nov. Additionally, two specimens from the Tembat Forest Reserve, Hulu Terengganu, Kelantan and another from Ulu Gombak, Selangor have been diagnosed as new the species. The latter specimen remained unidentified in the Bernice Pauahi Bishop Museum, Honolulu, Hawaii since its collection in June 1962. Morphological and molecular analyses demonstrate that S. sungaicolus sp. nov. forms a clade with the Indochinese species S. maculatus, S. indicus, and S. tersus and is the sister species of the latter. Sphenomorphus sungaicolus sp. nov. can be differentiated from all other members of this clade by having a smaller SVL (66.5–89.6 mm); 39–44 midbody scale rows; 72–81 paravertebral scales; 74–86 ventral scales; a primitive plantar scale arrangement; and 20–22 scale rows around the tail at the position of the 10th subcaudal.

Keywords: Reptilia, Integrative taxonomy, New species, Scincidae, Southeast Asia, Sundaland





Etymology.Sungai” is the Malaysian word for river and “colus” is derived from the Latin meaning “dweller in”. The specific epithet sungaicolus refers the obligate riparian nature of this new species.

Distribution. Sphenomorphus sungaicolus sp. nov. is known from Hutan Lipur Sekayu, Hutan Lipur Chemerong, and the Tembat Forest Reserve, Hulu Terengganu, Terengganu, Peninsular Malaysia—localities east of the Banjaran Titiwangsa. Localities on the western side of the Banjaran Titiwangsa are FRIM and Ulu Gombak, Selangor and the Korbu Forest Reserve, Perak to the north (Fig. 1). It is likely this species has a greater distribution throughout Peninsular Malaysia similar to what has been reported for other species of lizards whose distribution wraps around the southern end of the Banjaran Titiwangsa (Grismer 2011).


Juvenile Sphenomorphus sungaicolus sp. nov.  from the Korbu Forest Reserve, Perak. 
(not collected) Photograph by Z. Dzulkafly.  flickr.com  

Natural history. Sphenomorphus sungaicolus sp. nov. is a lowland species not known to occur above 300 m in elevation and found only in riparian areas coursing through lowland dipterocarp forest. All specimens were found along the edges of watercourses. ZRC.2.4915 from FRIM was found on boulders next to a large stream (Leong et al. 2002) and the holotype was found at night running in water at the edge of a small stream amongst rocks at Hutan Lipur Sekayu. The Hutan Lipur Chemerong and Ulu Gombak specimens were collected from along riverbanks. The Hulu Terengganu specimens were collected from pitfall traps located approximately 2.5–3 meters from the edge of a river. Sphenomorphus sungaicolus sp. nov. is the first obligate riparian skink known from Peninsular Malaysia. A hatchling S. sungaicolus sp. nov. from the Korbu Forest Reserve, Perak (Fig. 7) was photographed along the sandy edge of a rocky stream at an elevation of approximately 300 m (Zaharil Dzulkafly in litt. 2015).


Sumarli, Alexandra, L. L. Grismer, JR. P. L. Wood, Amirrudin B. Ahmad, Syed A. Rizal, Lukman H. B. Ismail, Nur A. M. Izam, Norhayati Ahmad and Charles W. Linkem. 2016. The First Riparian Skink (Genus: Sphenomorphus Strauch, 1887) from Peninsular Malaysia and Its Relationship to other Indochinese and Sundaic Species.
Zootaxa. 4173(1); 29–44.  DOI: 10.11646/zootaxa.4173.1.3