Eutropis innotata ( Blanford, 1870 )

Thasun Amarasinghe, A. A., Ganesh, S. R., Patel, Harshil, Deuti, Kaushik, Campbell, Patrick D., Palot, M. Jafer, Karunarathna, Suranjan, Abinawanto, A. & Supriatna, Jatna, 2021, Taxonomy and predicted distribution of a rare Indian skink, Eutropis innotata (Blanford, 1870) (Reptilia: Scincidae) with the redescription of its holotype, Zootaxa 4981 (3), pp. 577-592 : 582-586

Eutropis innotata ( Blanford, 1870)

( Figs. 4 , 5 ; Table 3 )

Euprepes innotatus Blanford, 1870

Euprepes innotatus — Theobald 1876

Mabuia innotata — Boulenger 1887, 1890

Mabuya innotata — Smith 1935, Tikader & Sharma 1992, Sharma 2002

Mabuya innotatus (sic.)— Das 1996, Chandra & Gajbe 2005

Eutropis innotata — Mausfeld et al. 2002, Mausfeld & Schmitz 2003, Rao et al. 2010, Srinivasulu et al. 2014, 2016, Deuti et al. 2020

Holotype. Adult male, NHMUK 1946.8 .19.2, tail broken, SVL 54.7 mm, collected from “Pem Ganga Valley, S.E. Berár ” (= Penganga Valley of Godavari River Basin , Yavatmal District, Maharashtra), India, by Dr. W. T. Blanford, date unknown [Note: the locality is recorded in the museum registry as “Godavery Valley”].

Diagnosis. A species of Eutropis inhabiting parts of the Deccan plateau, characterised as follows: morphologically most similar to E. dissimilis in body colouration, but lacks vertebral striping (a pair of black and white vertebral stripes in E. dissimilis ); five keels on the mid dorsal scales (two), a nuchal pair (absent). In addition, E. innotata is similar to E. bibronii and E. nagarjunensis by having a transparent disc on the lower eyelid, but is distinguishable from those two species by having no vertebral stripes (present), and having 32–34 midbody scale rows (28–30 in E. bibronii ), 56–60 ventrals (less than 52 ventrals), 45–50 paravertebrals (less than 41), 14–18 lamellae beneath the forth toe (20–24 in E. nagarjunensis ), a single pair of smooth nuchals (two pairs of keeled nuchals), smooth temporals (keeled in E. bibronii ), and absence of postnasal scale (present). Furthermore, E. innotata can be distinguished from any other known Eutropis species by having the following combination of characters: adult SVL of 54.7 mm, absence of mid dorsal longitudinal stripes, five keels on the mid dorsal scales, a smooth nuchal pair, three pre-auricular lobules, a transparent disc on the lower eyelid, 32–34 midbody scale rows, 56–60 ventrals, 45–50 paravertebrals, 14–18 lamellae beneath forth toe, absence of postnasal scale, and smooth temporal scales.

Redescription of holotype. Head moderately large, HL 23.3% of SVL, narrow, HW 55.8% of HL, HW 13.0% of SVL, indistinct from neck; snout short, ES 31.8% of HL, ES 57.1% of HW, slightly convex in lateral profile; rostral shield large, hemispherical, distinctly visible from above, posterior margin of midpoint rounded; frontonasal slightly contacting rostral; frontonasal wide, lateral border narrowly touching first loreal; prefrontals widely separated, contacting frontal and frontonasal, length equals frontonasal length, laterally contacting both loreal scales, posterior border contacting first supraciliary, first supraocular and frontal; frontal large, longer than wide, rounded posteriorly, length slightly shorter than frontoparietals and interparietal combined; frontoparietals two, in contact, longer than interparietal; parietals large and completely separated by interparietal, contacting pretemporal scales anterolaterally; all head scales smooth; single pair of smooth nuchals, overlapping middorsally. Nostril large and placed posterior of nasal; supranasal single, slightly in contact; loreals two, anterior contacting nasal, supranasal, frontonasal, prefrontal, posterior loreal, and first and second supralabials; posterior loreal longer than anterior loreal in the longitudinal axis, contacting prefrontal, first supraciliary, preocular, anterior presubocular, second and third supralabials; presuboculars two; eye large, ED 25.9% of HL; eye diameter greater than eye–tympanum distance, TYE 92.4% of ED, pupil rounded; interorbital distance broad; postoculars two, small; supraoculars four, all wide, second longest in the longitudinal axis and widest in the transverse axis, 1 st supraocular in contact with prefrontal, 2 nd in contact with frontal and frontoparietal, 3 rd in contact with frontoparietal, 4 th in contact with frontoparietal and parietal; supraciliaries seven; eyelid moveable, lower eyelid covered with a transparent disc.

Supralabials seven (eight on right side), fifth largest and at the mid orbit position, and contacting granular scales of lower eyelid; temporals smooth, single pretemporal; two primary temporals, secondary temporals three; infralabials six; ear opening large, approximately one third ED, deep, nearly round; three tiny pre-auricular lobules on anterior tympanum, below two larger and prominent. Mental large; postmental single, large; two pairs of chin shield, each pair separating in midline by gular scales, first chinshield in contact with second and third infralabial scales, the second pair in contact with third and fourth infralabials.

All dorsal scales are slightly quinquecarinate (three keels prominent) but varies from three to five keels along the body; all scales slightly imbricate; body slender, elongate; midbody scale rows 33; paravertebral scales 50; ventrals 58; preanal scales enlarged, four.

Forelimbs short, hind limbs relatively long, FEL 19.4% of SVL, TBL 11.1% of SVL; thigh longer, TBL 57.0% of FEL; dorsal surfaces of fore and hind limbs slightly tricarinate; subdigital lamellae of toe IV: 17; relative length of fingers IV> III> II> V> I; those of toes IV> III> V> II> I.

Tail broken (89.0 + 8.4 mm), median scale row of subcaudals subequal.

Coloration. After more than 150 years in preservative, dorsal head, body and tail light olive green, limbs light brown; a white dorsolateral stripe starting over the eye to the shoulder level, disappearing afterwards; another similar white stripe below beginning at supralabials and ending at the shoulder, these stripes with brown margins, and the area in between these stripes dark brown visible as a lateral band, fading after shoulder level; rest of the dorsum uniform without any colour patterns or vertebral stripes, a few rows of anterior body scales with darker margins; venter white, except limbs which are brownish.

The live colouration is unknown, except for the colour description provided by Rao et al. (2010), who stated “Overall colouration of the skink was light golden brown, dorsal side without vertebral markings or streaks. A black dorso-lateral stripe between the eyes and base of the tail present, and the same was bordered by white line, which gradually faded posteriorly. Venter of the specimen was yellowish-white”. In addition, Deuti et al. (2020) provided a colour image of a live individual of this species from Yavatmal, Maharashtra, but the white margin of the black dorso-lateral stripe is not as prominent as in the holotype specimen.

Distribution and habitat. Eutropis innotata is only known from five localities (seven sightings) since its description in 1870 ( Fig. 5 ). Among these, four sightings (including collected specimens) were made recently: specimens, ZSI/R 284 and 1078 were collected in 1994, specimen ERMR-45a collected in 2002 [not examined by us, reported in Rao et al. (2010)], and the recent photograph in Deuti et al. (2020). Based on the reported localities of this species, it occurs in dry deciduous forests and scrublands. The predicted distribution range of this species is much wider than its known locations, especially in the south-central parts of the Deccan plateau (see under the habitat prediction).

Conservation status. The current conservation status of this species is Data Deficient (DD), which was correctly determined a decade ago (Sept 2010), but with the suggestion that this species may occur in many more localities than was known at the time ( Srinivasulu & Srinivasulu 2013). The application of the IUCN Red List criteria ( IUCN Standards and Petitions Subcommittee 2019) with the updated distribution data shows that E. innotata is restricted to an area of occupancy (AOO) of 175 km 2 recorded from seven localities within a 325,000 km 2 extent of occurrence (EOO). Given the extent of occurrence, the widespread distribution of dry deciduous forests and scrubland habitats, and the wide range of habitat predictions, E. innotata should be considered as a “Least Concern” (LC) species. Also, we opine that the reason for low reporting rates of this species is due to it being overlooked. The low reporting rate for E. innotata seems more likely to be due to the dorsum colour pattern exactly resembling that of E. carinata (see Fig. 4 and Discussion). Within the known distributional range of E. innotata , there are many protected areas such as Gundla Brameshwaram Sanctuary (Andhra Pradesh); Kanha National Park, Pench National Park (Madhya Pradesh); Yavatmal Wildlife Sanctuary, Melghat Tiger Reserve, Bhimashankar Jyothirlinga Wildlife Sanctuary (Maharashtra); and Amarkantak-Achanakmar Wildlife Sanctuary (Chhattisgarh). While we do not deny the on-going habitat degradation outside protected areas, the conditions appear stable inside protected areas (Malavia et al. 2010; Reddy et al. 2015). Recent studies on the conservation status of the habitat as a whole reveal degradation threats that are not as alarming as they might be ( Agarwala et al. 2016; Neelakantan et al. 2019; Sahu et al. 2008; Yadav et al. 2012), largely due to it being the stronghold of a tiger population ( Joshi et al. 2013; Sharma et al. 2013). Therefore the rate of habitat destruction across the entire species range would be insufficient to indicate a population decline of>30% over the last 3 generations (i.e. the threshold for consideration under Criterion A). Also we believe that there are more than 1,000 individuals within the predicted geographic range, and therefore it doesn’t qualify under Criterion D. As we do not have the population decline information to consider Criterion C, at the moment, our description relates mostly to Criterion B.

Figures

FIGURE 4. Eutropis innotata holotype (NHMUK 1946.8.19.2): (A) full body in dorsolateral aspect; head in (B) dorsolateral, (C) lateral (note the transparent disc on the lower eyelid), and (D) ventral aspects; and (E) foot and toes.

FIGURE 5. The map of India showing the Godavari River Basin and the current known distribution of E. innotata based on museum specimens and published literature: 1Type locality, “Pem Ganga valley, S.E. Berár” (Penganga Valley, Yavatmal), 2S.E. Berár (Yavatmal District), 3Korba, Bilaspur, 4Chinnamanthanala, Gundla Brahmeswaram Metta Sanctuary, 5Melghat Tiger Reserve, 6Bhaka Devi, Bhimashankar Wildlife Sanctuary, 7Yavatmal (locality of recent photograph published in Deuti et al. 2020).