Cyrtodactylus maelanoi, Grismer & Rujirawan & Termprayoon & Ampai & Yodthong & Wood & Oaks & Aowphol, 2020

Grismer, L. Lee, Rujirawan, Attapol, Termprayoon, Korkhwan, Ampai, Natee, Yodthong, Siriporn, Wood, Perry L., Oaks, Jamie R. & Aowphol, Anchalee, 2020, A new species of Cyrtodactylus Gray (Squamata; Gekkonidae) from the Thai Highlands with a discussion on the evolution of habitat preference, Zootaxa 4852 (4), pp. 401-427 : 410-424

Cyrtodactylus maelanoi sp. nov.

Mae La Noi Bent-toed Gecko

( Figs. 5–7 )

Holotype. Adult male ZMKU R 00857 (field tag AA 03726) collected on 22 March 2017 at 2100 hrs by Piyawan Puanprapai, Attapol Rujirawan, Siriporn Yodthong, Natee Ampai, and Elyse S. Freitas from the Tha Pha Pum Subdistrict, Mae La Noi District , Mae Hong Son Province, Thailand (18.34223°N, 98.02317°E WGS; 991 m in elevation).

Paratypes. The paratypes ZMKU R 00852–00856 (field tag AA 03721–25) bear the same data as the holotype. The remaining paratypes ZMKU R 00858–00860 (field tag AA 06195–97) bear the same locality data as the holotype but were collected by Attapol Rujirawan, Siriporn Yodthong, Korkwan Termprayoon, Natee Ampai on 13 June 2018 .

Diagnosis. Cyrtodactylus maelanoi sp. nov. differs from all species in the C. sinyineensis group by having the combination of 7–9 supralabials; six or seven infralabials; 29–37 paravertebral tubercles; 16–19 longitudinal rows of dorsal tubercles; 27–33 ventral scales ventral scales; 9–12 expanded subdigital lamellae on the fourth toe; 11–14 unmodified subdigital lamellae on the fourth toe; 22–24 total subdigital lamellae on the fourth toe; 24–28 enlarged femoral scales; a total of 8–13 pore-bearing femoral scales in males; 4–8 enlarged precloacal scales; four or five pore-bearing precloacal scales in males; three rows of enlarged post-precloacal scales; approximately five or six jagged dorsal body bands; 11 light-colored caudal bands (n=2); 11 dark-colored caudal bands (n=2); raised and strongly keeled dorsal tubercles that extend beyond base of tail; enlarged femoral and precloacal scales nearly the same size and continuous; pore-bearing femoral and precloacal scales not continuous; medial subcaudals two to three times wider than long and not extending onto lateral side of tail; iris reddish; nuchal loop lacking an anterior azygous notch, and bearing a jagged posterior border; dorsal bands not bearing paravertebral elements, wider than interspaces, bearing lightened centers, edged with white tubercles; dark markings in dorsal interspaces; dark caudal bands wider than light caudal bands; light caudal bands in adults bearing dark-colored markings; light-colored caudal bands not encircling tail; and mature regenerated tail not spotted ( Table 5).

Description of holotype. Adult male SVL 75.2 mm ( Fig. 5 ); head moderate in length (HL/SVL 0.28), wide (HW/HL 0.73), flat (HD/HL 0.39), distinct from neck, triangular in dorsal profile; lores inflated, prefrontal region concave, canthus rostralis rounded; snout elongate (ES/HL 0.39), rounded in dorsal profile, broad in lateral profile; eye large (ED/HL 0.27); ear opening oval (EL/HL 0.11); eye to ear distance greater than diameter of eye; rostral rectangular, partially divided dorsally, bordered posteriorly by supranasals and one internasal, laterally by first supralabials; external nares bordered anteriorly by rostral, dorsally by supranasals, posteriorly by two postnasals, and ventrally by first supralabials; 8(R,L) rectangular supralabials extending to below midpoint of eye; 6(R,L) infralabials tapering posteriorly to commissure of jaw; scales of rostrum and lores slightly raised, larger than granular scales on top of head and occiput; scales on top of head and occiput intermixed with small tubercles; dorsal superciliaries weakly pointed and directed laterally; mental triangular, bordered laterally by first infralabials and posteriorly by large left and right trapezoidal postmentals which contact medially for 50% of their length posterior to mental; one row of enlarged chinshields, outermost row bordering first four infralabials; gular and throat scales granular, grading posteriorly into larger, subimbricate pectoral and ventral scales.

Body relatively short (AG/SVL 0.39) with well-defined ventrolateral folds; dorsal scales small, raised and interspersed with large, raised, semi-regularly arranged, strongly keeled tubercles; tubercles extend from top of head onto base of tail just beyond the postcloacal swelling; tubercles on nape smaller than those on body; 30 paravertebral tubercles; approximately 17 longitudinal rows of dorsal tubercles; 28 flat, subimbricate, ventral scales larger than dorsal scales; eight enlarged precloacal scales; five pore-bearing precloacal scales not separated on the midline by a poreless scale; three rows of large, post-precloacal scales; and no deep precloacal groove or depression.

Forelimbs moderate in stature, relatively short (FL/SVL 0.17); slightly raised, juxtaposed scales of forearm larger than those on body, intermixed with large tubercles; palmar scales slightly raised, juxtaposed; digits welldeveloped, relatively long, inflected at basal, interphalangeal joints; digits narrow distal to inflections; widened proximal subdigital lamellae extend onto palm; slight webbing at base of digit; claws well-developed, sheathed by a dorsal and ventral scale at base; hind limbs more robust than forelimbs, moderate in length (TBL/SVL 0.21), covered dorsally by small, raised, juxtaposed scales intermixed with large pointed tubercles and bearing flat, slightly larger imbricate scales anteriorly; ventral femoral scales flat, imbricate, much larger than dorsals; one row of 14(R)13(L) enlarged femoral scales and enlarged precloacal scales continuous; enlarged femoral scales nearly equal in size; small, postfemoral scales form an abrupt union with larger, flat ventral scales on posteroventral margin of thigh; 5,6(R,L) pore-bearing femoral scales not continuous with pore-bearing precloacal scales; subtibial scales flat, imbricate; plantar scales raised; digits relatively long, well-developed, inflected at basal, interphalangeal joints; 11(R,L) transversely expanded subdigital lamellae on fourth toe proximal to joint inflection that do not extend onto sole, 13(R,L) unmodified subdigital lamellae distal to inflection; and claws well-developed, base of claw sheathed by a dorsal and ventral scale.

Tail nearly complete, gracile in proportions, 115.1 mm in length, 8.1 mm in width at base, tapering to a point, TL/SVL (1.42); dorsal scales of tail flat, forming indistinct whorls; median row of transversely expanded subcaudal scales three times as wide as long, not extending onto lateral subcaudal region; three enlarged postcloacal tubercles at base of tail on hemipenal swellings; and postcloacal scales large, flat.

Color pattern ( Figs. 5 , 6 ). Dorsal ground color of head, body, limbs, and tail yellowish-brown; top of head and rostrum nearly unicolor, bearing areas of slightly darker, diffuse irregularly shaped markings; nuchal loop smooth posteriorly with two posterior projections, not divided medially; approximately five dark jagged body bands bearing lightened centers, lacking paravertebral elements, edged with whitish tubercles extend from the shoulder to the presacral region; lighter colored interspaces between bands bear darker markings; whitish tubercles scattered on flanks; sacral and postsacral bands continue onto the tail to form five black caudal bands that are wider than the five light-colored caudal bands; light-colored caudal bands bear dark markings and do not encircle tail; limbs bear distinct, dark-colored irregularly shaped markings; posterior one-third of tail regenerated with dark mottled pattern; gular scales bearing only two or three black stipples; black stippling in throat, pectoral region, and anterior portion of belly more dense; subcaudal region darkly mottled, posterior one-third grey with faint mottling.

Variation. The paratypes closely resemble the holotype in dorsal banding and nuchal loop pattern ( Fig. 6 ). The nape band are more prominent in ZMKU R 00858–00860 and ZMKU R 00855. Paratypes ZMKU R 00858–00860 , 00852 , 00855–00857 are darker overall. Paratypes ZMKU R 00853, 00859–00860 have regenerated tails. Paratype ZMKU R 00854 is missing the posterior one-thrid to one-half of the tail. Additional variation in meristic and mensural characters are presented in Table 6 .

Distribution. Cyrtodactylus maelanoi sp. nov. is known only from the type locality from the Tha Pha Pum Subdistrict, Mae La Noi District, Mae Hong Son Province, Thailand (18.34223°N, 98.02317°E WGS; 991 m in elevation; Fig. 1 ).

Etymology. The specific epithet “ maelanoi ” is a toponym of the type locality Mae La Noi. The recommended vernacular name in English is Mae La Noi Bent-toed Gecko.

Natural history. All lizards observed were abroad at night ( Fig. 7 ) in the vicinity of a waterfall ( Fig. 8 ). Lizards were found on the ground, the walls of a building, and on granite rocks and within their cracks. Lizards were also seen on tree trunks as high 70–200 cm above the ground and on a twig approximately 160 cm above the ground. These observations clearly indicate that Cyrtodactylus maelanoi sp. nov. is a habitat generalist. No hatchlings of gravid females were observed indicating that at least the period of March through June is probably outside the reproductive season of this species.

characters Clade 2 Clade 1 amphipetraeus aequalis bayinnyiensis chaunghanak- waensis dammathetensis dattkyaikensis naungkayain- gensis maelanoi sp. inthanon sinyineensis taungwineensis welpyanensis doisuthep Supralabial scales (SL) mean (±SD) Range 9.0 (0.00) 9 8.1 (0.46) 7–9 8.0 (0.84) 7–9 9.4 (0.71) 8–11 9.0 (0.00) 9 8.3 (0.58) 8 or 9 8.3 (0.58) 8 or 9 8.1 (0.60) 7–9 11.0 (1.00) 10–12 9.7 (0.57) 9 or 10 9.1 (0.86) 7–10 8.3 (0.6) 8 or 9 11.0 (1.0) 10–12 n 9 37 5 24 3 3 3 9 3 3 14 3 3 Infralabial scales (IL) Mean (±SD) Range 7.0 (0.00) 7 6.8 (0.53) 6–8 6.2 (0.44) 6 or 7 7.9 (0.50) 7–9 7.7 (0.58) 7 or 8 6.3 (0.57) 6 or 7 7.0 (0.00) 7 6.3 (0.50) 6 or 7 9.3 (0.58) 9 or 10 8 (0.00) 8 7.00 (0.39) 6–8 7.0 (0.00) 7 9.5 (1.5) 8–11 n 9 37 5 24 3 3 3 9 3 3 14 3 3 Paravertebral tubercles (PV) Mean 34.7 32.0 26.0 32.5 31.7 34. 0 34.3 31.1 / 33.7 30.3 31.7 / (±SD) Range (0.50) 34 or 35 (1.64) 29–36 (0.71) 25–27 (0.98) 31–36 (1.15) 31–33 (0.00) 33–35 (0.58) 34 or 35 (2.37) 29–37 / / (0.00) 33–35 (0.84) 29–32 (1.5) 30–33 / n 9 37 5 24 3 3 3 9 / 3 14 3 / Longitudunal rows of body tubercles (LT) Mean (±SD) Range 17.9 (0.78) 17–19 20.6 (1.42) 18–23 17.4 (01.14) 16–19 19.5 (1.47) 17–22 14.3 (1.15) 13–15 19.0 (1.00) 18–20 17.3 (1.54) 16–18 15.5 (0.87) 16–19 19. 0 (1.00) 18–20 15 (0.00) 15 18.7 (0.61) 18–20 16.0 (0.00) 16 19.7 (0.58) 19 or 20 n 9 37 5 24 3 3 3 9 3 3 14 3 3 Ventral scales (VS) Mean (±SD) Range 28.3 (0.71) 28–30 24.5 (1.68) 22–31 25.6 (1.52) 24–28 25.4 (1.10) 23–27 26.7 (1.53) 25–28 25.3 (0.58) 25 or 26 27.0 (0.00) 27 28.4 (1.94) 27–33 30.7 (2.89) 29–34 28 (0.00) 27–29 32.3 (2.02) 30–36 29.3 (1.20) 28–30 32.0 (3.00) 29–35 n 9 37 5 24 3 3 3 9 3 3 14 3 3

nov

Comparisons. Cyrtodactylus maelanoi sp. nov. (n=9) differs from all other species of the C. sinyineensis based on various combinations of character states ( Table 5). In clade 1, it differs from C. inthanon , C. sinyineensis , and C. taungwineensis in having significantly fewer supralabials and from these species plus C. welpyanensis in having significantly fewer infralabials ( Fig. 4 ; Table 4). It differs further from C. sinyineensis , C. taungwineensis , and C. welpyanensis having significantly fewer precloacal scales; from C. sinyineensis it differs significantly in having fewer enlarged femoral scales; it differs further from C. taungwineensis by having significantly fewer ventral scales ( Fig. 4 ; Table 4). Cyrtodactylus maelanoi sp. nov. may differ further from its sister species C. inthanon in having 24–28 enlarged femoral scales versus 29–32 in C. inthanon and they plot completely separate in the PCA and DAPC analyses ( Fig. 3 ). Increases in sample sizes may indicate that some of these character differences are not statistically significant whereas other differences may be statistically significant. Differences in color pattern among all species of the C. sinyineensis group are listed in Table 5.

Figures

FIGURE 1. Distribution of the species of the Cyrtodactylus sinyineensis group in Thailand and Myanmar.

FIGURE 3. A. PCA of the species of clade 1 of the Cyrtodactylus sinyeensis group based on meristic characters. Plot points with the white borders are the centroids. B. DAPC of same. C. Histograms of the factor loadings of the characters contributing the most to the variation along PC1, PC2, and PC3.

FIGURE 4. Boxplot comparisons of discrete meristic characters among the species of clade 1 of the the Cyrtodactylus sinyeensis group. Light blue circle is the mean and the black horizontal bars are the medians. Asterisks denote species bearing statistically significant mean differences from C. maelanoi sp. nov.

FIGURE 5. Holotype of adult male Cyrtodactylus maelanoi sp. nov. (ZMKU R 00857) immediately after euthanasia. Above. Ventral view of pelvic region showing enlarged femoral and precloacal scale and pore arrangement. Middle. Dorsal view show- ing nuchal loop, dorsal band, and caudal patterns. Below. Ventral view showing belly and subcaudal coloration.

FIGURE 6. Cyrtodactylus maelanoi sp. nov. type series. From left to right top panel: ZMKU R 00853 (field tag AA 03722), ZMKU R 00857 (field tag AA 03726), ZMKU R 00859 (field tag AA 06196) and ZMKU R 00860 (field tag AA 06197); bottom panel: ZMKU R 00856 (field tag AA 03725), ZMKU R 00854 (field tag AA 03723), ZMKU R 00858 (field tag AA 06195), ZMKU R 00852 (field tag AA 03721) and ZMKU R 00855 (field tag AA 03724).

FIGURE 7. Uncatalogued specimen of Cyrtodactylus maelanoi sp. nov. photographed in situ at the type locality of Tha Pha Pum Subdistrict, Mae La Noi District, Mae Hong Son Province, Thailand.

FIGURE 8. Habitat of Cyrtodactylus maelanoi sp. nov. at the type locality of Tha Pha Pum Subdistrict, Mae La Noi District, Mae Hong Son Province, Thailand.