Eutropis tammanna, Das, Indraneil, Silva, Anslem De & Austin, Christopher C., 2008

Das, Indraneil, Silva, Anslem De & Austin, Christopher C., 2008, A new species of Eutropis (Squamata: Scincidae) from Sri Lanka, Zootaxa 1700, pp. 35-52 : 38-47

Eutropis tammanna sp. nov.

Figures 1–5

Mabuya species I. Das & A. de Silva. 2005. Photogr. Guide. Snakes & Other Rept. Sri Lanka:118.

Holotype. Department of National Museums, Colombo (formerly, the Ceylon Museum, CMS), registration number awaited (field number CCA 2365), adult male, from 17 mile post, Buttala (06º40'53"N, 81º16'14"E; altitude 125 m asl), Kataragama Road, Uva Province, Sri Lanka; C. C. Austin and A. de Silva, collectors, 7 November 2002.

Paratypes. CMS, registration number awaited (field number CCA 2370), adult female, from Koruppa (07º21'36"N, 80º59'35"E; altitude 100 m asl), Mahiyangana, Uva Province, Sri Lanka; C. C. Austin and A. de Silva, collectors, 9 November 2002; CMS, registration number awaited (field number CCA 2385), adult female, from Rambewa (08º26'59"N, 80º30'32"E; altitude 137 m asl), North Central Province, Sri Lanka; C. C. Austin and A. de Silva collectors, 11 November 2002.

Other material. CMS 2007.16.0 3 (ex -ID 8904), CMS 2007.16.0 4 (ex -ID 8903), CMS 2007.16.0 5 (ex -ID 8915), three specimens, from Tammanna Estate (08º00'56.1"N, 79º51'19.5"E; altitude 22 m asl), Puttalam Peninsula, North West Province, Sri Lanka, A. de Silva and I. Das, collectors, 23 October 2004. One adult male and two adult females.

Morphological diagnosis. A small (SVL to 52.3 mm) species of Eutropis , diagnosable from congeneric species in having the following combination of characters: transparent window-like disk absent on lower eyelids; prefrontals in broad contact; a single pair of nuchals; postnasal absent; ear opening larger than adjacent scales; dorsal scales with 6–7 keels; midbody scale rows 28–29; paravertebral scale rows 37–40; ventral scales 41–48; lamellae under fourth toe 15–16; dark labial bars present in both sexes, which are more distinct in males; dark postocular stripe absent; males brown on dorsum, with dark flanks speckled with cream; females similar to males, the pattern less contrasting; lacking paired series of black markings, pale vertebral stripes or dark longitudinal stripes on dorsum. In addition, the rostral, labials, and gular region of presumed breeding males are flame scarlet.

Molecular diagnosis. Eight hundred and thirty four base pairs of the mitochondrial ND2 gene from six species of Eutropis show diagnostic characteristics that delimit E. tammanna from other Eutropis . Site 1 of the aligned data presented here corresponds to site 4076 in the Eumeces egregius complete mtDNA genome Gen- Bank sequence (AB016606.1). Eutropis tammanna has an uncorrected pair-wise difference of 8.9% from its sister taxa (a population of E. macularia ; Appendix 2). Eutropis tammanna is included in a well supported clade of Eutropis from Sri Lanka and E. macularia from Bhutan ( Fig. 8 ). The three individuals of E. tammanna included in the genetic analyses show seven molecular synapomorphies (node 1, Fig. 8 ): site 4 is a G (third codon position), site 10 is a G (third codon position), site 259 is a T (third codon position), site 319 is a T (third codon position), site 445 is a G (third codon position), site 461 is a G (first codon position resulting in an amino acid change to valine), and site 569 is a T (first codon position change but not resulting in an amino acid change). The sister taxon to E. tammanna is E. macularia from Bhutan (RMNP 11, cited by Das and Palden, 2000), and this lineage is united by eight molecular synapomorphies (node 2, Fig. 8 ): site 57 is a T (second codon position resulting in an amino acid change to isoleucine in E. macularia (RMNP 11), and E. tammanna (CCA 2385), and a change to valine in E. tammanna (CCA 2365 and CCA 2370), site 100 is a T (third codon position), site 118 is a C (third codon position), site 296 is a G (first codon position resulting in an amino acid change to valine), site 425 is a T (first codon position resulting in an amino acid change to serine), site 591 is a C (second codon position resulting in an amino acid change to threonine), site 681 is an A (second codon position resulting in an amino acid change to tyrosine), and site 697 is a C (third codon position). Finally, the well supported monophyletic clade including E. tammanna and three distinct E. macularia lineages is supported by five synapormorphies (node 3, Fig. 8 ): site 50 is a T (first codon position resulting in an amino acid change to serine), site 263 is a G (first codon position resulting in an amino acid change to glutamic acid), site 497 is a A (first codon position resulting in an amino acid change to methionine), site 592 is a C (third codon position), site 766 is a third codon position and has either C or T for this clade while all other taxa have either A or G, and site 780 is an A (second codon position resulting in an amino acid change to either lysine or asparagine).

Description of holotype. A well-preserved adult male, with detached, original tail; SVL 51.9 mm, TL 93.2 mm; snout short (IN/IO ratio 0.57), obtuse, slightly projecting beyond lower jaws; nostril laterally oriented, oval, situated closer to snout-tip than to orbit (E-N/E-S ratio 0.61); head relatively short, slightly longer than wide, HL 8.6 mm, HW 7.6 mm (HL/HW ratio 1.13), slightly flattened, HD 5.0 mm (HL/HD ratio 1.72); rostral broad, projecting well onto snout; posterior border of rostral semicircular; supranasals rectangular, separated from each other, in contact with rostral, frontonasal trapezoid, wider than long; prefrontals large, in broad contact; frontal elongated, arrow-head shaped, wider anteriorly; frontoparietals in broad contact; interparietal single, shorter than frontonasal; parietals separated by interparietal; a pale parietal eye spot situated at posterior half of interparietal; four supraoculars; no contact between supraocular I and frontal; supraocular II most posterior supraocular to contact frontal; six supraciliaries; nostrils located between nasal and anterior loreal; postnasal absent; loreals squarish, two in number; equal in height; anterior loreal higher than long; posterior loreal larger than the anterior; two presuboculars, separating supralabial IV from lower eyelid; seven supralabials (supralabial V contacting orbit of eye); six postsuboculars; two postoculars; all temporals keeled; two primary temporals followed by an upper and lower secondary temporal separated by a well established intervening tertiary temporal (2 + 2 separated pattern of Greer and Broadley, 2000: Fig. 2 C); one pair of nuchals; six infralabials; one scale separates second pair of enlarged chin shields; three scales separate third pair of chin shields; enlarged chin shields contact infralabials; external ear opening larger than adjacent scales, oval, with numerous lobules, the most distinct of which is a spinose one on the anterior edge, oriented towards the posterior; pupil rounded; lower eyelid lacking a clear window, supraciliaries five; scales on upper eyelid small, numbering 11; scales on upper row of lower eyelid small, numbering 13; tongue short, with a slight notch anteriorly, teeth small, somewhat obtuse.

Body relatively slender, BW 9.0 mm (BW/SVL ratio 0.17); head indistinct from neck and from body; 40 paravertebral rows; 48 ventrals; skin not fragile; body scales cycloid, with 6–7 distinct keels; 28 transverse scale rows at midbody; 80 subcaudals; on dorsum, keels start from posterior edge of parietals; scales on flanks with weak keels; those on venter smooth; abdominal scales larger than throat and pectoral scales, the median ventral scales also enlarged relative to scales on flanks; preanals enlarged, lateral pair of preanals overlap median preanal; no irregular series of scales covering posterior aspect of thigh; tail relatively long (TL/SVL ratio 1.80), tip acute, tail base not wider than rest of tail, gradually tapering to a point; median row of subcaudals not enlarged relative to adjacent scales.

Limbs relatively short; pentadactyle and clawed; scales on limbs weakly bicarinate; lamellae obtusely tuberculate and enlarged; adpressed limbs reach level of carpals; lamellae under finger I– 4; II– 8; III– 10; IV– 11; V– 6; lamellae under toes I– 5; II– 8; III– 12; IV– 16; V–8.

Holotype colouration– adult male. In preservative, dorsum medium-brown, forehead unicoloured; torso with scattered black blotches; venter, including gular region unpatterned yellowish-ivory; infralabials unbarred; supralabials with dark vertical bars more distinct posterioriorly, beyond the level of orbit of eye, forming vertical bars that reach the angle of the jaws and continue as a blackish-brown flank stripe; dark flank stripe five scales wide, comprising scales that are typically bicoloured ivory (on top) and black (on bottom); on sides of tail, the dark stripe breaks up into four dark stripes that traverse the length of the tail; upper surfaces of forelimbs with darker variegations and cream blotches; dorsal surfaces of limbs and tail unbanded pale brown; undersurfaces of limbs and tail ivory; tongue grey.

Paratype colouration– adult female. In preservative, based on CMS uncatalogued (ex - CCA 2385), dorsum bronze brown, the supralabials, especially the posterior edge with faint grey vertical bars, reminiscent of the pattern of the male, with greater contrast; a dark brown-grey stripe commences from posterior edge of tympanum, broadens on the flanks, and continues along the tail, where it becomes faint at approximately the level of midtail, forming three narrow lines; gular, pectoral and abdominal regions unpigmented yellowishcream; dorsal surfaces of limbs and tail unbanded pale brown; undersurfaces of limbs and tail ivory; tongue grey.

Colouration (in life). Based on CMS 2007.16.0 4, adult male and CMS 2007.16.0 3, adult female. Adult male dorsum Chestnut (#32), flank stripe Dusky Brown (#19) with Sulfur Yellow (#157) speckles; rostral, anterior supralabials, infralabials and gular region Flame Scarlet (#15). Adult female dorsum glossy, iridescent Walnut Brown (#221B); flank stripe Blackish Neutral Gray (#82), the pale flecks Salmon Color (#6). In both sexes, pupil is black and iris is Flesh Color (#5).

Measurements (in mm). Holotype with variation shown in type series in parentheses. SVL 51.9 (49.1– 51.9, mean 51.10 ± 1.01); HL 8.6 (7.2–8.8, mean 8.20 ± 0.50); HW 7.6 (6.5–7.6, mean 6.93 ± 0.34); HD 5.0 (4.6–5.0, mean 4.73 ± 0.13); BW 9.0 (9.0–11.5, mean 10.07 ± 0.74); TBL 6.9 (6.2–8.0, mean 6.43 ± 0.23); ED 3.2 (2.8–3.2, mean 2.93 ± 0.13); IN 2.4 (1.9–2.6, mean 2.30 ± 0.21); IO 4.2 (4.0–4.4, mean 4.20 ± 0.12); E-S 4.4 (3.4–4.4, mean 3.87 ± 0.29); E-N 2.7 (2.2–2.7, mean 2.37 ± 0.17); N-S 1.3 (1.0–1.3, mean 1.10 ± 0.10); A- G 27.3 (26.0–28.1, mean 27.13 ± 0.61); and TL 93.2 (70.3–93.2, mean 81.30 ± 6.63).

Variation in squamation and coloration. Holotype with variation shown in type series in parentheses. Transverse scale rows at midbody 28 (28–29, mean 28.33 ± 0.33); paravertebral rows 40 (37–40, mean 38.33 ± 0.88); ventral scale rows 48 (41–48, mean 45.00 ± 2.08); supralabials 7 (no variation); infralabials 6 (6–7, mean 6.33 ± 0.33); subcaudals 80 (75–85, mean 80.00 ± 2.89); and lamellae under toe IV 16 (15–16, mean 15.67 ± 0.33). Sexual dichromatism observed includes the flame scarlet rostral, labial and gular colours of the single male described above, in addition to the relatively contrasting flank stripe. In females, the overall colouration of dorsum is comparatively sobre, lacking the bright colours on the lips and throat, and the vertical dark bars near the angle of the jaws are faintly indicated.

Etymology. Derived from Pali, a Middle Indo-Aryan dialect, and the source of Sinhala and several east Indian languages, meaning bronze, the overall colour of dorsum of the new species. Tammanna is also the point where King Vijaya (543–504 B.C.), who founded the first Sinhalese empire, landed on the island, close to the Tammanna Estate, where we collected additional material of the new species.

Ecological and distributional notes. CMS 2007.16.03–04 were collected during the day, from under fallen coconuts and discarded thatch material in the vicinity of a coconut and cashew nut plantation, <50 m from the shore ( Fig. 6 ). The following herpetofaunal species were found in sympatry at Puttalam: ( Microhylidae ): Uperodon systoma ; ( Agamidae ): Calotes versicolor , Sitana ponticeriana ; ( Gekkonidae ): Geckoella yakhuna ; Hemidactylus frenatus ; ( Scincidae ): Eutropis carinata , Lygosoma punctata ; ( Colubridae ): Oligodon arnensis , and ( Elapidae ): Naja naja . CCA 2370 and CCA 2385 contained two eggs each (measurements not taken due to obvious distortion at preservation).

The new species has been collected at the following additional localities: 1 km N Udappuwa, North Western Province, 07º58'24.4"N, 79º47'15.9"E, alt. 12 m asl; vicinity of Kalpitiya, North Western Province, 07º58'23.8"N, 79º47'17"E, alt. 3 m asl; Kandalama, Central Province, 07º20'36"N, 80º51'32"E, alt. 200 m asl, Pothana, Kimbissa (Sigiriya), Central Province, 07º56'37.6"N, 80º42'40.2"E, alt. 190 m asl, and Rajarata University Park, Mihintale, North Central Province, 08º21'11.7"N, 80º30'09.6"E, alt. 108 m asl. The elevational distribution of the new species is thus from sea level to 190 m asl. ( Fig. 7 ).

Comparisons. Six nominal species of Eutropis have been reported from Sri Lanka (de Silva, 1998; Das and de Silva, 2005). In making comparisons, only opposing suite of characters are listed. These are: beddomei (Jerdon, 1870: SVL to 55 mm; head narrow; midbody scale rows 30–32; dorsal scales with 3–5 keels; lamellae under toe IV 12–15; dark longitudinal stripes on dorsum and throat of adult males not red; bibronii (Gray, 1839: SVL to 50 mm; transparent window on lower eyelids; two pairs of nuchals; a light vertebral stripe present; and throat of adult males not red); carinata (Schneider, 1801: SVL to 125 mm; midbody scale rows 30–34; dorsal scales with 3–5 keels; dark labial bars absent; broad postocular stripe present; dark flank stripe lacks pale spots; and males lack flame scarlet areas on labial and gular regions); floweri ( Taylor, 1950: SVL to 56 mm; dorsal scales tricarinate; midbody scale rows 30–32, dorsum with a paired series of ca. 20 short black marks from level of axilla to some distance along tail and labial; and gular regions of adult males not flame scarlet); E. macularia (Blyth, 1853: SVL to 75 mm; ear opening smaller than adjacent scales on temporal region; throat of adult males not flame scarlet; and at least in the Sri Lankan population [cryptic species have been indicated within this complex- see Ota et al., 2001; Mausfeld and Schmitz, 2003], a narrow [one scale wide], pale dorsal stripe extends from the top of postocular region, across body to the length of tail, adjacent to a broad [three scales wide] laterodorsal stripe); and madaraszi (Méhely, 1897: SVL to 77 mm; midbody scale rows 32; a pale dorsolateral stripe from supralabials to midtail; adpressed hind limb reaches axilla; an irregular series of scales covering posterior aspect of thigh; and throat of adult males not flame scarlet).

To the north-west of the arid plains of Sri Lanka lies the tip of the Indian Peninsula, where four of the species of Sri Lankan Eutropis also occur: beddomei, bibronii, carinata and macularia . The southern hill country of Peninsular India, comprising the Western and Eastern Ghats, is home to four additional congeners ( Smith, 1935; Welch et al., 1990; Das, 2002), with which the new Sri Lankan species is here compared: Eutropis allapallensis (Schmidt, 1926; distribution: western, central and south-western India, including Goa, Gujarat, Tamil Nadu, Maharashtra and Kerala: SVL to 75 mm; frontoparietals fused; prefrontals not in contact; temporal scales smooth; preanals not enlarged; and gular regions not flame scarlet); E. clivicola ( Inger, Shaffer, Koshy & Bakde, 1984; distribution: Kerala State: SVL to 55 mm; prefrontals in narrow contact; dorsal scales with five weak keels; lamellae under fourth toe 17–19; a narrow, dark vertebral stripe and labial; and gular regions not flame scarlet); E. gansi (Das, 1991: distribution: Tamil Nadu State: SVL to 62.6 mm; prefrontals not in contact; midbody scale rows 30; a two-scale wide dark grey lateral stripe and labial; and gular regions not flame scarlet); and E. nagarjuni Sharma, 1969 : distribution: Andhra Pradesh: SVL to 51 mm; prefrontals not in contact with each other; three pairs of nuchals and postnasals present and labial; and gular regions not flame scarlet).

Although the island nation of Sri Lanka is generally known to have a distinctive biota, this is localised to regions with high precipitation, specifically, the highlands, which is located around the west-central and south-western portions of the island ( Fig. 7 ; see also Bossuyt et al., 2004). The high endemicity of this region has been attributed in part to the intervening xeric lowlands of northern and eastern Sri Lanka and those of southern India ( Das, 1996) and land connection, mediated by sea level lowering, between the now separated landmasses existed as recently as 10,000 years before present ( Rohling et al., 1998). The known distribution of the new species of Eutropis described lies within the dry and intermediate zones of Sri Lanka (described in Fernando, 1984; Panabokke, 1996), suggesting that herpetological sampling in such areas outside known biodiversity hotspots may yield other herpetological novelties.

Figures

FIGURE 1. Dorsolateral views (A and B) of Eutropis tammanna sp. nov. (holotype; CMS uncatalogued; ex - CCA 2365), adult male, in life.

FIGURE 2. Dorsolateral view of Eutropis tammanna sp. nov. (paratype; CMS uncatalogued; ex - CCA 2370), adult female, in life.

FIGURE 3. Dorsolateral view of Eutropis tammanna sp. nov. (paratype; CMS uncatalogued; ex - CCA 2385), adult female, in life.

FIGURE 4. Head and forebody of male (Top; CMS 2007.16.04) and female (Bottom; CMS 2007.16.03) of Eutropis tammanna sp. nov.

FIGURE 5. Head scalation in the holotype of Eutropis tammanna sp. nov. (CMS uncatalogued, ex - CCA 2365). Top left. Dorsal view; Bottom left. Lateral view; and Right. Ventral view. Scale marker = 1 mm.

FIGURE 6. Habitat of Eutropis tammanna sp. nov. at Puttalam, north-western Sri Lanka.

FIGURE 7. Satellite map of Sri Lanka, showing the collection localities for Eutropis tammanna sp. nov. References: A = Buttala, Uva Province; B = Koruppa, Central Province and C = Rambewa, North Western Province. Climate contours redrawn from Panabokke and Kannangara (1996).

FIGURE 8. Bayesian phylogram of the phylogenetic relationships of selected species of Eutropis. The tree shows Bayesian branch lengths and nodal support is MP bootstraps (left) for 1,000 replicates, ML bootstraps (centre) for 500 replicates, and Bayesian posterior probabilities (right). Outgroups include the Australasian genera Carlia, Emoia, Eumeces (GenBank), Lamprolepis, and Sphenomorphus. Node 1 is supported by seven molecular synapomorphies, Node 2 is supported by eight molecular synapomorphies, and Node 3 is supported by five molecular synapomorphies (see molecular diagnosis).