Cnemaspis alwisi, Mendis Wickramasinghe & Munindradasa, 2007

Mendis Wickramasinghe, L. J. & Munindradasa, D. A. I., 2007, Review of the genus Cnemaspis Strauch, 1887 (Sauria: Gekkonidae) in Sri Lanka with the description of five new species, Zootaxa 1490 (1), pp. 1-63 : 5-6

Cnemaspis alwisi sp. nov.

Holotype. NMSL 2004.9.1, Adult male, 39.92 mm SVL, from Dolukanda, Kurunegala, Sri Lanka, (N 07º 37’ 07.8” E 80º 24’ 50.3”, elevation 152m), 23.12.2003, collected by L. J. Mendis Wickramasinghe and D. A. I. Munindradasa.

Paratypes. NMSL 2004.9.2 , Adult female, 37.84 mm SVL; NMSL 2004.9.3 , Adult male, 32.99 mm, the same date, locality and collectors.

Diagnosis. A medium-sized Cnemaspis (snout to vent length 33–40 mm in adults), which can be distinguished from all known congeners by the following combination of characters: Postmentals separated by a small scale; nostrils are not in contact with first supralabial; 15 supra labials to angle of mid-orbit position and end of jaw at nine supra labials; 32 interorbitals; throat scales smooth; dorsal tubercles 90–92 small, rounded, pentagonal or hexagonal; absence of groups of carinated large scales in dorsal body; spine-like tubercles absent on flanks; 28 midventrals; ventral scales smooth and imbricate; mid-subcaudals large; no preanal pores; 7–8 femoral pores on each side; 13 subdigital lamellae and 3 basal lamellae in the 4 th finger; 15 subdigital lamellae and 3 basal lamellae in the 4 th toe; segmented tail; dorsal part of tail with flushed and smooth scales, rarely intermixed with large semicircular prominent tubercles.

Description of Holotype. Adult male ( Fig.2 , 12A , 16A , 20A , 24A and 28A ) snout to vent length 39.92 mm, head depressed and narrow (HD / HLJ 0.37), head elongated and large (HLJ / SVL 0.27), distinct from neck. Snout long (SE / HW 0.72), longer than eye width (EW / SE 0.41). Eye relatively large (EW / HLJ 0.19). Ear opening small (EL / HLJ 0.09), inter ear distance is greater than width of eye (EE / EW 3.27).

Rostral is large with a groove penetrating 3/4 of the scale. There are two internasals of the same size. Supranasal and postnasal consist of one smooth circular scale each and are bigger than the nostril, but smaller than the internasal. Head is covered with large circular, pentagonal or hexagonal shaped tubercle scales from snout to posterior margin of interorbital area, and are rarely intermixed with elongated scales and with small granulated scales up to neck. The size of tubercle scales becomes progressively smaller from the snout to interorbital area. Similar scales (still smaller than that on the snout) are located in lower and upper interorbital areas and, a set of very small scales are located in the parietal area. There are 32 interorbital scales of which mid scales are an intermix of rounded and elongated scales of different sizes. Supraciliaries are slightly larger than lower interorbital scales. Nostril is oval and not connected with supralabials. Nostril and the first supralabial are separated by a postnasal. The loreal region is convex and is covered with 18 large, circular (rarely intermixed with pentagonal or hexagonal scales) and smooth tubercle scales. There are 15 supralabials at the base of the jaw, with 9 at the mid orbit point. The first supralabial is larger than the others. The rest becomes progressively small. Dorsal tubercles are smaller than lower interorbitals. Those are rounded, pentagonal or hexagonal in shape and of similar size. There are 92 dorsal tubercles at the mid region of the body which are rounded, pentagonal or hexagonal in shape. Spine-like tubercles are absent on flanks. Smooth and conical subimbricates present on lower and upper parts of the flank are larger than dorsal body scales. Dorsal parts of forelimb and hindlimb are covered with rounded, pentagonal and hexagonal shaped scales slightly larger than that of the body. Dorsal part of tail is covered with flushed and smooth scales larger than dorsal body, rarely intermixed with large semicircular prominent tubercles. Tail is segmented with a dorsal groove. Mental scale is large and sub-triangular. A pair of rounded and pentagonal or hexagonal postmentals (smaller than the mental) is present on either side. The first postmental pair is separated by a small scale, and is connected with the first infralabial. The second postmental pair is smaller, and is connected with the first and second infralabials. There are seven infralabials towards the jaw end, with six of them towards the mid orbit point. Infralabials become progressively smaller in size towards the anterior end. Ear holes are oval shaped, bigger than nostrils, but smaller than eyes. There are 26–27 scales between eye and ear. Scales in the throat are smooth, pentagonal or hexagonal in shape. Anterior scales are larger than the posterior scales. Gular scales are smooth. Mid ventral area consists of 28 scales, which are smooth, imbricate and smaller than postmental scales. Scales in ventral portion of fore and hind limbs are smooth, with scales on hind limb being relatively larger than that of forelimb. There are 7–8 femoral pores and no preanal pores present. Preanal scales are equal or smaller than anal scales. There are 64 subcaudals where mid subcaudals are hexagonal in shape and larger than the other scales on the tail. The lower border appears to be elongated-diamond in shape. Keels absent in subcaudals. Digits are slender, elongated and clawed. Distal sub-digital formulae include 4>5>3>2>1 (fingers) and 4>3>5>2>1 (toes) ( Fig.24.A .).

Colour in life. Body colour in the dorsal side is dark grey. There are irregular yellowish white dots in the interorbital area. A segmented transverse line and an ‘M’ mark, yellowish white in colour are present on the dorsal head between internasal and interorbital areas. A black patch is present on the neck. Four dots and two ‘M’ mark, of yellowish white colour are present in a line along the vertebra from mid neck to hind limbs. The supraciliaries are yellow. The eye pupil is circular and black with the surrounding being yellow. The lateral view of head and neck consists of three black line segments—one from nasal to mid eye in loreal region, the other along lower parietal boundary and the third from back of eye to neck on temporal region which is prominent than the other two, in a grey background with spots in supralabial, lower neck and jaw lower areas, while spots in lower jaw being more prominent. The ventral view of the throat is light yellow. Three faded white stripes are present on each lower and upper arm in a dark grey background. The black stripe formula of 2,3,4,5 and 3 is present on fingers in a yellowish white background. The ventral view of lower and upper arm is greyish white. The yellowish white spots in upper flank and white spots in lower flank are present in mid lateral view. The mid ventral view is greyish white. Three segmented stripes are present on each femur and tibia in a brownish yellow background. The black stripe formula of 2,3,3,4 and 4 is present on toes in a yellowish white background. The ventral aspect of femur and tibia is greyish white in colour. The original part of the tail is dark grey, with 9 irregular white patches. The ventral side of tail is greyish white.

Colour in alcohol. The background colour changes from brownish grey and yellow to white.

Etymology. The species is an eponym in the Latin genitive singular honouring Lyn De Alwis, for his initiative in igniting a research culture in the country leading to Conservation of Wildlife resources. The vernacular names assigned for the species nov. are Alwisge diva huna, Alwisin pahal palli and Alwis’s day gecko in native languages Sinhala, Tamil and in English respectively.

Remarks. C. alwisi sp. nov. is congener with C. ranwellai and C. scalpensis from morphological characters. However, C. alwisi can easily be distinguished from both by having two internarsals and low count of lamella in forth finger and toe, and femoral pores, and from C. ranwellai by the separated postmental (more than 90% of C. ranwellai population in the type locality shows contacted postmental), the dorsal tubercle count and ventral scale count, and from C. scalpensis by the intraorbital count, dorsal tubercle count and ventral count, and also from the morphometric analysis. In different specimens the ventral body colour varies from white to yellow. Often C. alwisi is found among boulders and the body colour takes the colour pattern of lichens that are abundant on these wet boulders to blend with the environment where they live. In addition to the type locality C. alwisi is found in Retigala and Maragala mountains, and Nilgala area of Sri Lanka.

Figures

FIGURE 2. Holotype male of C. alwisi sp. nov. 39.92 mm SVL (NMSL2004.9.1)

FIGURE 12. The dorsal, lateral and ventral view of the head of, A. C. alwisi sp. nov. 39.92 mm SVL (NMSL2004.9.1), B. C. ranwellai 30.50 mm SVL (NMSL2004.1.1) and C. C. scalpensis 34.23 mm SVL (NMSL20061101).

FIGURE 16. The dorsal, lateral and ventral view of the mid body of, A. C. alwisi sp. nov. 39.92 mm SVL (NMSL2004.9.1), B. C. ranwellai 30.50 mm SVL (NMSL2004.1.1) and C. C. scalpensis 34.23 mm SVL (NMSL20061101).

FIGURE 20. The dorsal and lateral view of the upper body and the ventral view of the lower body of, A. C. alwisi sp. nov. 39.92 mm SVL (NMSL2004.9.1), B. C. ranwellai 30.50 mm SVL (NMSL2004.1.1) and C. C. scalpensis 34.23 mm SVL (NMSL20061101).

FIGURE 24. The ventral view of the hand, foot and tail of, A. C. alwisi sp. nov. 39.92 mm SVL (NMSL2004.9.1), B. C. ranwellai 30.50 mm SVL (NMSL2004.1.1) and C. C. scalpensis 34.23 mm SVL (NMSL20061101).

FIGURE 28. The plot of factor scores 1 and 2 of multivariate Principal Components Analysis based on unrotated coefficients of log-transposed morphometric characters of C. alwisi sp. nov., C. ranwellai and C. scalpensis indicating the uniqueness of the new species among other species found associative from morphological comparison.