Wednesday, November 1, 2017

[Herpetology • 2017] Tytthoscincus temasekensis • A New Species of Swamp-dwelling Skink (Tytthoscincus) from Singapore and Peninsular Malaysia


 Tytthoscincus temasekensis
 Grismer, Wood, Lim & Liang, 2017 

RAFFLES BULLETIN OF ZOOLOGY65 

Abstract

 Tytthoscincus temasekensis is a new species of swamp-dwelling skink from Singapore and the vicinity of Tanjung Malim, Perak, Peninsular Malaysia and the third species in the swamp clade of Tytthoscincus. It is distinguished from all other species of Tytthoscincus by the combination of having two loreals; two postsupralabials; 10–12 superciliaries; four supraoculars; interparietal contacting the 2nd–4th supraoculars; a shallow, pigmented tympanum; slightly enlarged, isolated, pectoral scales; 27–29 midbody scale rows; 55–65 paravertebral scales; 54–63 ventral scales; 9–11 subdigital lamellae on the fourth toe; keeled, subdigital lamellae; and a dorsal pattern of light-coloured stripes and/or linearly arranged spots. The growing diversity of the swamp clade in Singapore and Peninsular Malaysia begins to underscore the underappreciated contribution of swamplands to herpetological endemism and diversity as well as the need for its conservation.

 Key words. Scincidae, Tytthoscincus, Singapore, Malaysia, swamp forests, new species

Fig. 2. Tytthoscincus temasekensis sp. nov.  adult holotype (ZRC 2.6490) from Pasir Laba Road, Singapore.; juvenile paratype (ZRC 2.7111) from Upper Seletar Reservoir Park, Singapore (Photograph by Nick Baker).

TAXONOMY 

The molecular and morphological data indicate thus far that the Tytthoscincus populations from Singapore and Tanjung Malim are conspecific and well-differentiated from T. sibuensis and T. panchorensis. They are therefore described below as:

 Tytthoscincus temasekensis, new sp.

Diagnosis. Tytthoscincus temasekensis sp. nov. can be differentiated from all other species of Tytthoscincus in Peninsular Malaysia by having the combination of two loreals, two postsupralabials, 9`1 or 10`2 superciliaries, four supraoculars; interparietal contacting 2nd–4th supraoculars, a shallow, pigmented tympanum, slightly enlarged pectoral scales, 27–29 midbody scale rows, 55–65 paravertebral scales, 54–63 ventral scales, 9–11 subdigital lamellae on the fourth toe, keeled, subdigital lamellae, and a dorsal pattern of light-coloured stripes and/or linearly arranged spots. All characters are scored across all other Tytthoscincus and species of Sphenomorphus suspected of being Tytthoscinus in Grismer et al. (2016a: 237) and Karin et al. (2016: 416).

Non-types. Tytthoscincus temasekensis. ZRC 2.3277 (juvenile) from North Selangor Peat Swamp kilometer marker 34 on road to Tanjung Malim, Selangor, Peninsular Malaysia (approximately N 03°42.383′, E 101°09.115′; 20 m elevation) collected by NUS 1991–92 Zoology Honours Class on 17 June 1991. ZRC 2.3377 (juvenile) from North Selangor Peat Swamp kilometer marker 47 at Sungai Besar Road on road to Tanjung Malim, Selangor, Peninsular Malaysia (approximately N 03°41.472′, E 101°14.062′; 15 m elevation) collected by D. S. L. Chung in April 1993. ZRC 2.7152 from the Nee Soon swamp-forest, Singapore collected by H. H. Tan and others on 23 October 1999.



  
Fig. 2. Tytthoscincus temasekensis sp. nov.   juvenile paratype (ZRC 2.7111) from Upper Seletar Reservoir Park, Singapore (Photograph by Nick Baker).; uncataloged specimen from 3 km south of the Nee Soon Swamp, Singapore (Photograph by Noel Thomas).

Distribution. Tytthoscincus temasekensis, new species, is known from lowland areas in Singapore and near Tanjung Malim, Perak, Peninsular Malaysia (Fig. 1). Natural history. Tytthoscincus temasekensis has been found in lowland dipterocarp forests but is far more common along stream banks in peat and freshwater swamp forests up to at least 37 m in elevation (Lim, 1998; Serin, 2015; Fig. 3). Specimens near Tanjung Malim were inadvertently collected while hand-netting for fishes in small streams which may indicate semi-aquatic proclivities as noted by Baker (2013) who states “An example of about 5 cm was seen among forest leaf litter at the edge of a shallow stream. It swam in a sinuous motion across the stream, coming to rest on the opposite side partly submerged, with only the front part of its head including the eyes and nostrils emerged.” ZRC 2.7111 was collected while crossing a paved road running through lowland forest. A juvenile (ZRC 2.6859) was taken from the gut of an Aheatulla mycterizans found dead on Old Upper Thomson Road.

 Etymology. The specific epithet temasekensis is derived from the word Temasek meaning ‘Sea Town’ in Old Javanese and represents the earliest recorded name of a settlement in Singapore. The suffix -ensis is Latin meaning ‘of or from a place.’ The specific epithet is in reference to the type locality being on the island of Singapore. The suggested common name is the Singapore swamp skink.


L. Lee Grismer, Perry L. Wood, Jr., Kelvin K. P. Lim and Lim J. Liang. 2017. A New Species of Swamp-dwelling Skink (Tytthoscincus) from Singapore and Peninsular Malaysia.  RAFFLES BULLETIN OF ZOOLOGY65; 574–584. 

  

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