Cnemaspis psychedelica, Grismer, Lee, Tri, Ngo Van & Grismer, Jesse L., 2010

Grismer, Lee, Tri, Ngo Van & Grismer, Jesse L., 2010, A colorful new species of insular rock gecko (Cnemaspis Strauch 1887) from southern Vietnam, Zootaxa 2352, pp. 46-58 : 48-55

publication ID	https://doi.org/ 10.5281/zenodo.275617
DOI	https://doi.org/10.5281/zenodo.6205630
persistent identifier	https://treatment.plazi.org/id/6332A47C-7330-FFFD-F9C9-FD30F3D62670
treatment provided by	Plazi
scientific name	Cnemaspis psychedelica
status	sp. nov.

Treatment

Cnemaspis psychedelica sp. nov.

Psychedelic Rock Gecko Figs. 2–6 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6

Holotype. Adult male ( UNS 0444) collected on 24 June 2009 from Hon Khoai Island, Ca Mau Province, Ngoc Hien District, Vietnam (08° 26.098 N, 104° 49.536 E) by Ngo Van Tri, Jesse L. Grismer, and L. Lee Grismer.

Paratypes. The collection date and locality of the paratypes UNS 0 445 (female), 0 446 (male), 0447–40 (females), and 0 449 (male) are the same as that of the holotype.

Diagnosis. Cnemaspis psychedelica differs from all other Southeast Asian species of Cnemaspis in having a color pattern in both sexes and all age classes of bright-orange forelimbs, hands, feet and tail; bright-orange flanks bearing three or four yellow, transverse bars; a bright-yellow reticulum on the neck overlaying thick, black streaks; and a greenish head. It differs further from all other species of Cnemaspis in having the unique combination of adult males reaching at least 75.3 mm SVL, adult females reaching at least 72.2 mm SVL; having seven or eight supralabials and 5–7 infralabials; very large mental scale followed by three postmental scales and extending posteriorly to the level of the fourth or fifth infralabial scales; dorsal forearm scales and dorsal tubercles keeled; subtibials, ventrals, and subcaudals smooth; 32–48 paravertebral tubercles; tubercles on flanks not linearly arranged; caudal tubercles restricted to single paravertebral rows; one or two postcloacal tubercles; no precloacal scales; greatly enlarged femoral scales; large, plate-like subtibial scales; enlarged, submetatarsal scales beneath first toe; and 25–28 subdigital lamellae on fourth toe. These differences are summarized across all other Cnemaspis in Grismer et al. (2008a: TABLE 1) and Grismer and Chan (2009: TABLE 1).

Description of holotype. Adult male; SVL 71.6 mm; head oblong in dorsal profile, moderate in size (HL/ SVL 0.27), moderate in width (HW/SVL 0.18), flat (HD/HL 0.39), distinct from neck; snout short (ES/HL 0.47), concave in lateral profile; postnasal region constricted medially, flat; scales of rostrum smooth to weakly keeled, raised, larger than similarly shaped scales on occiput; distinct, supraorbital ridges; prominent frontorostral sulcus; canthus rostralis smoothly rounded; eye large (ED/HL 0.20); extra-brillar fringe scales small in general but elongate anteriorly; pupil round; ear opening oval, much taller than wide; rostral concave dorsally, dorsal 50% divided by longitudinal groove; rostral bordered posteriorly by two large supranasals and laterally by first supralabials and nostrils; 8R,9L horizontally keeled supralabials slightly tapering in size posteriorly; 6R,L infralabials, decreasing gradually in size posteriorly; nostrils elliptical, oriented dorsoposteriorly; bordered posteriorly by three small scales; mental very large, triangular, extending to level of fourth infralabial, bordered posteriorly by three postmentals, the lateral postmentals one-half the size of the rostral, the medial postmental very small; gular scales small, smooth to faintly keeled, juxtaposed and slightly raised to subimbricate; throat scales, smooth, slightly raised.

Body robust; small, weakly keeled, dorsal scales equal in size throughout body, intermixed with slightly larger, weakly keeled tubercles more or less longitudinally arranged, especially in vertebral region; tubercles extend from just anterior of forelimb insertion to base of tail and are smallest anteriorly; 32 paravertebral tubercles; pectoral and abdominal scales smooth, subimbricate, posterior abdominal scales slightly larger; abdominal scales much larger than dorsals; precloacal pores and depression absent; femoral pores absent; forelimbs moderately long, robust, dorsal scales keeled; ventral scales of forearm smooth, subimbricate; palmar scales smooth, juxtaposed, raised; digits long with an inflected joint; claws recurved; subdigital lamellae unnotched; lamellae wide throughout length of digits; interdigital webbing absent; fingers increase in length from first to fourth with fifth shorter than fourth; digits one and two missing on right hand; hind limbs longer and thicker than forelimbs, robust in stature; dorsal scales small, keeled, raised, juxtaposed; ventral scales of hind limbs smooth, imbricate; two rows of greatly enlarged smooth, flat, femoral scales extending from hind limb insertion to knee joint and increasing in size distally ( Fig. 3 View FIGURE 3 ); subtibials smooth, flat and platelike covering entire subtibial region ( Fig. 3 View FIGURE 3 ); plantar scales smooth, slightly raised, subimbricate; enlarged submetatarsal scales beneath first metatarsal ( Fig. 3 View FIGURE 3 ); digits elongate with an inflected joint; claws recurved; subdigital lamellae unnotched; lamellae wide throughout length of digits ( Fig. 3 View FIGURE 3 ); interdigital webbing absent; toes increase in length from first to fourth with fourth being slightly longer than fifth; 27L, 28R subdigital lamellae on fourth toe; caudal scales weakly arranged in whorls; caudal scales smooth, flat, juxtaposed; shallow, middorsal and single lateral furrows; median row of transversely enlarged, smooth, subcaudal scales on original part of tail (anterior 35.8 mm), more narrow transversely enlarged median row of subcaudals on regenerated portion of tail (posterior 44.1 mm) bearing a midventral furrow; caudal tubercles occur only in single paravertebral rows on original portion of tail; regenerated portion of tail covered with smooth, flat, randomly arranged, juxtaposed scales; two enlarged, postcloacal tubercles on lateral surfaces of hemipenal swellings at base of tail; tail 1.1% of SVL.

Coloration (in life). Dorsal ground color of head anterior to posterior margin of eyes greenish yellow; occipital region and nape covered with a bright-yellow reticulum overlaying thick, black streaks, some of which begin as thin, postorbital stripes; dorsal ground color of trunk and upper limbs immediately proximal to the elbow and knee joints blue-gray to light purple; hands, feet, and distal portion of limbs bright-orange; ventral portion of flanks bright-orange bearing four, short, transverse, yellow bars; tail bright-orange; all ventral surfaces beige, generally immaculate except for faint stippling on throat and gular region. In alcohol, coloration is generally uniform brown dorsally and beige ventrally, except for a slightly darker gular region.

Variation. Variation in scale counts and measurements are shown in TABLE 1. Color pattern in Cnemaspis psychedelica is remarkably consistent among the paratypes and other uncollected specimens photographed in situ (see Figs. 4,5,6), showing no differences between sexes or age classes. In comparison to the holotype (UNS 0444), black streaking on the neck is slightly more distinct in UNS 0 445 and 0 449 and is very faint in UNS 0 446. The yellow reticulum on the nape in UNS 0 446 is also slightly less prominent. UNS 0 446 also has a patch of skin missing from the dorsal surface of the right thigh. Another feature of this species is its lack of sexual dimorphism in other aspects of its morphology. Males do not have precloacal pores and their hemipenal swellings at the base of the tail are remarkably small, making it somewhat difficult to differentiate males from females without a gonadal examination.

Distribution. Cnemaspis psychedelica is known only from Hon Khoai Island, Ngoc Hien District, Ca Mau Province, Vietnam in Rach Gia Bay 18 km off the southern tip of Point Can Mau ( Fig. 1).

Natural History. Hon Khoai Island is a small (~ 8 km 2) island lying 18 km south off Point Ca Mau off the Ca Mau Peninsula in Rach Gia Bay ( Fig. 1). It reaches approximately 320 m at its highest point and slopes moderately to the sea, lacking some of the precipitous, rocky bluffs characteristic of some of the other nearby islands. It maintains a thick forest cover that is dominated by primary, semideciduous forest on its slopes and upper elevations with disjunct, mangrove swamps fringing its coastlines. Hon Khoai Island’s granite basement results in scattered, small to massive, boulder outcroppings across the lower elevations of the island that provide the microhabitat for Cnemaspis psychedelica . The vegetation surrounding the granite outcroppings is usually dense and composed of relatively small trees ( Fig. 7).

UNS UNS UNS UNS UNS UNS

0 445 0 446 0 447 0 448 0 449 0 444

paratype paratype paratype paratype paratype holotype

Sex female male female female male male SVL 72.2 75.3 54.7 69.2 55.7 71.6 TL 79.5r 70.1r 71.1 60.5r 58.2 77.9r TW 9.5 9.5 7 8.8 7.6 9.6 FL 12.9 12.2 9.8 12.5 11.1 12.7 TBL 15.3 15.8 12 14 12.5 15.4 AG 29.3 29.7 21.7 28.4 21.4 26.2 HL 19.2 19.4 14.4 19.2 15.7 19.4 HW 13 13.8 10.2 12 9.6 12.7 HD 8.3 8.3 5.8 7.3 6 7.6 ED 3.6 3.9 3.1 3.6 3 3.8 EE 5.5 6.1 3.9 5.5 4.3 5.5 ES 9.5 9.4 7.2 9.3 7.2 9.2 EN 7 8.2 5.6 6.8 5.5 11.9 IO 5.9 5.5 5.1 5.7 4 4.8 EL 2.4 2 1.2 2.4 2.1 2 IN 1.9 1.9 1.4 1.7 1.5 2.1 Supralabials 8 8 8 8 7 8 Infralabials 6 5 7 6 5 6 No. paravertebral tubercles 38 36 48 34 37 32 No. of postcloacal tubercles 1 2 1 1 2 2 No. of 4th toe lamellae 26 28 25 27 26 28 Cnemaspis psychedelica is a relatively large, robust, diurnal, lowland, saxicolous species. We observed several lizards of both sexes and all size class abroad on large, granite boulders in the shade of the forest canopy from 0800–1930 hrs. Some lizards were seen sitting exposed in filtered sunlight apparently basking. Lizards would retreat into rock cracks, beneath ledges, or between rocks upon our approach. It was not uncommon to see 2–5 lizards together on the same rock. Lizards showed no preference for any particular plane of orientation, be it vertical, horizontal, or inverted nor did they restrict their activity to only deeply shaded, surfaces as do many other species of Cnemaspis ( Chan & Grismer 2008; Das & Grismer 2003; Grismer & Chan 2008, 2009; Grismer & Das 2006; Grismer & Ngo 2007; Grismer et al. 2008a, b; 2009). During the evening hours from 1930 to 2400, lizards were more difficult to find, although the much larger Cyrtodactylus sp. nov. (Grismer et al. in prep) were very common, occupying nearly every conceivable niche and most likely out competing C. psychedelica . During the day when C. psychedelica was abundant, Cyrtodactylus sp. nov. could not be found. At night, most C. psychedelica were restricted to deeper areas of crevices and were only occasionally seen outside the rock cracks. Those that were seen abroad were only on inaccessible, more sheltered, vertical surfaces beneath large overhangs ( Fig. 7). During this period as well, lizards were often seen in pairs or trios ( Fig. 4 View FIGURE 4 ) and their coloration was even more brilliant with the trunk becoming a light purple ( Figs. 4 View FIGURE 4 , 5 View FIGURE 5 vs. Fig. 6 View FIGURE 6 ). The only individual observed not on rocks was found sleeping on a leaf at night ( Fig. 5 View FIGURE 5 ). We observed hatchlings, gravid females carrying two eggs, and egg clusters on the undersides of overhanging boulders. Other reptiles observed were Draco maculatus (LSUDPC 5270), Cyrtodactylus sp. nov (Grismer et al. in prep.), Gekko gecko (LSUDPC 5090), Gehyra mutilata (LSUHC 4086), Hemidactylus frenatus (LSUDPC 5091), H. platyurus (LSUDPC 5093), Dasia olivacea (LSUDPC 2959), Eutropis multifasciatus (LSUHC 3222), Scincella cf. reevesi (observed but not collected or photographed); Varanus salvator (LSUDPC 5123), Ahaetulla prasina (LSUDPC 5037), Chrysopelea ornata (observed but not collected or photographed), Lycodon capucinus (LSUDPC 3242), and Python reticulatus (reported by locals).

The most intriguing question concerning this species is why does it have such a bright, contrasting, incongruent color pattern? Unfortunately all we can offer is speculation. Its pattern has nothing to do with crypsis by way of disruptive coloration or camouflage because these relatively large, robust lizards are amazingly conspicuous, even at a distance of 20 m through the forest. Sexual selection can be ruled out because there is no sexual dimorphism. Our best guess at this point is that it may have something to do with aposematism. If so, this would rule out a diurnal, mammalian predator (being that most mammalian predators are color blind) that might be on the island and would suggest there is an avian predator instead.

The general abundance and diurnal saxicoloy of Cnemaspis psychedelica is similar to that of its close relative C. boulengeri (see below). On Con Dao Island during July of 2006, we observed several specimens of C. boulengeri abroad during the day on rocks in direct sunlight apparently basking. At night, however, this species was difficult to find and only observed deep within rock cracks ( Fig. 8 View FIGURE 8 ). Like C. psychedelica , lizards were most often seen together in pairs or trios both day and night ( Fig. 8 View FIGURE 8 ). Being that these two species are closely related (see below), we suspect this shared social behavior and penchant for basking has a phylogenetic component.

Comparisons. The unique color pattern of Cnemaspis psychedelica clearly and unequivocally separates it from all other species of Cnemapsis. Yet C. psychedelica bears a number of rare, morphological character states that support its close relationship with the other Vietnamese insular endemic, C. boulengeri , known from the Con Dao Islands off the east coast of the Ca Mau Peninsula, 195 km east of Hon Khoai Island. These two species are the only species that have caudal tubercles restricted to single paravertebral rows and enlarged femoral and subtibial scales ( Fig. 3 View FIGURE 3 ). This relationship is also supported by mtDNA data (Grismer et al. in prep.). A myriad of other characters differentiate C. psychedelica from other Cnemaspis . Most notable is its large, maximum SVL (> 69 mm) which separates it from all other species except C. limi , C. nigridius , and C. pemangilensis and high number of paravertebral tubercles (>34) which distinguishes it from all other species except C. boulengeri , C. kumpoli , C. nigridius , and C. pemanggilensis (see Grismer et al., 2008a:TABLE; Grismer & Chan, 2009: TABLE 1).