Japalura otai

Mahony, Stephen, 2009, A new species of Japalura (Reptilia: Agamidae) from northeast India with a discussion of the similar species Japalura sagittifera Smith, 1940 and Japalura planidorsata Jerdon, 1870, Zootaxa 2212, pp. 41-61 : 43-50

Japalura otai species new

( Figures 1–3 )

Holotype: ZSI 25217 (male), “Sairep, Lunglet District, Mizoram” (= Sairep (22°49'0 N, 92°49'0 E), Lunglei District, central Mizoram, northeast India), collector S.S. Saha, 19 April, 1995.

Paratypes: ZSI 25215 and 25216 (females), locality details as for holotype, collected on 16 and 19 April, 1995, respectively.

Diagnosis: This species differs from all species of the genus Japalura by the following combination of characters; small adult size (SVL male 46.4 mm, female 52.2–58.7 mm), tail length/SVL ratio 160.5–187.5%, 10–11 SL, 9–12 IL, 45–47 MD, 17–20 4 FingLam, 20–22 4 ToeLam, tympanum concealed, axillary fold present, raised nuchal and dorsal crest, transverse gular fold and distinct gular pouch absent, enlarged keeled dorsal scales present, body shape subquadrangular in cross section.

Description of Holotype: All measurements are provided in Table 1. Habitus subquadrangular in cross section, in profile snout steeply tapering to a pointed tip, rostral pentangular, approximately two times longer than deep, bordered by first SL and seven other scales, separated from the nasal by one scale. Nostril and nasal scale round, laterally positioned, bordered by 9 scales including SL two which is only narrowly in contact, 11/ 10 (left/right) smooth SL, scales of the loreal region irregularly arranged, flat, becoming weakly keeled below the orbit and on the temporal region, scales surrounding the eye, small and granular. Tympanum concealed. Canthals and supraciliaries imbricate, forming a laterally protruding supraorbital ridge. Dorsal head and snout scales heterogeneous in size, smooth anteriorly, becoming strongly keeled on the supraorbital region and rear of the head. Parietal eye not visible through the parietal which itself is approximately five times larger than surrounding scales. A short row of keeled scales form triangular dorsoventrally flattened spines along the upper posterior temporal region, the largest of which point posteriorly at the rear of the head. Directly above these is another single posteriorly oblique, dorsoventrally flattened spine. Elsewhere elongated keeled scales form one or two protruding spines at the rear of the jowls and a single small spine below the posterior axis of the upper and lower mandible. Mental triangular, approximately as wide as long, 12/11 (left/right) smooth IL, mental bordered posteriorly by a pair of elongated postmentals, subequal in length to the mental, broadly in contact with each other posteriorly and contacted by a second pair of shorter postmentals which are not in contact with each other, both postmental pairs are flat. Remaining gular scales imbricate to subimbricate and strongly keeled, subequal in size medially from the throat to chest region, no transverse gular fold or distinct gular pouch.

Ventral scales subimbricate, strongly keeled and arranged in regular rows. 45 MD, slightly enlarged and all with a strong medial keel. An additional row of moderately to strongly keeled scales form an almost continuous ridge from directly posterior to the enlarged temporal spines to the proximal portion of the tail. Dorsal scales are heterogenous in size, shape and texture. They primarily consist of small flat scales and distinctly larger keeled scales which are arranged into posteriorly pointing “V” shaped ridges of which the apex is the middorsal keel. There are approximately 6 primary “V” ridges regularly spaced along the dorsum, between each is a single incomplete, weakly keeled “V” ridge. The area between the head and shoulder is covered with small scales and forms a distinct shallow oblique axillary fold from the front of the shoulder to below the dorsolateral ridge. These small scales gradually increase in size over the flanks where there size J. otai J. planidorsata

male female female female

(holotype) (paratypes)

ZSI 25217 ZSI 25215 ZSI 25216 ZSI 5264 ZSI 16024 SVL 46.4 52.2 58.7 50.2 52.7 TailL 87 85 94.2 74.4 78.3 TailD 7.3 7.8 8 5.6 5.9 TailW 7.6 5.9 8.2 5.4 5.6 HL 15.1 17.8 20 16.2 16 HW 11.7 14.7 15.4 11.7 11.3 HD 7.7 9.2 9.9 7.7 8.7 IN 3.6 4 4.4 3.6 3.2 IO 7.1 9.1 8.4 7 7 TrL 19.2 24.3 25.2 26.5 25.5 PectW 8.5 11.6 13.3 10.4 9.5 PelvW 7.3 10.2 11.3 7.6 8.5 SnForL 20 20.5 25.7 18.9 20 UpArmL 9.6 10 12.3 8.6 9.2 LowArmL 8.9 8.9 10.3 7.6 8.5 HandL 9.7 11.6 12.7 9.5 10.1 4FinL 6.3 7.5 8.1 5.7 6.7 UpLegL 14.4 14.5 17.5 14 14 CrusL 13.1 14.3 16.1 12.9 13.3 FootL 18.3 20.6 21.8 16.4 17.5 4ToeL 10.6 10.4 12 9 9.5 SL 10/11 10 /10 10/ 10 10 11 IL 12/11 10 /9 10/ 10 9 11 MD 45 47 46 52 61 4FinLam 17 17 17 15 16 4 ToeLam 21 21 22 17 20

continued next page range is subequal to those of the dorsum, however both large and small scales are mostly keeled. The upper and lower forearms, hands and fingers are covered in longitudinal rows of strongly keeled distally pointed scales, those on the outer surfaces are larger and more strongly keeled grading into smaller, weakly keeled scales of the inner surfaces. Scales on the dorsal surface of the hind legs are heterogenous in size, ranging from small weakly keeled scales to large oblique trihedral spines. Ventral surfaces of the thigh, tibia, and dorsal and ventral surface of feet with keeled scales forming regular rows. 17 lamellae on finger IV and toe lamellae: 6 on I, 8 on II, 12 on III and 21 IV. Scales on the tail are strongly keeled ventrally, grading to weakly keeled dorsally. Hemipenal bulge distinctly enlarged.

Colouration in ethanol: Entire dorsal surface of the body from the back of the head extending onto the tail, between the dorsolateral keels is creamy white, dorsal surface of the head bicoloured, the posterior two thirds are a pale brownish cream, separated by a fine brown line from the anterior third of the head which is a darker shade of light brown. A broad cream stripe extends from the tip of the snout, along the upper lip to the level of the orbits, terminating at the rear axis of the jaw. Scales of the orbits are primarily dark brown with three distinct cream lines running from the lower eyelid to the cream lip-stripe, the posterior most stripe runs obliquely from the rear axis of the upper and lower eyelids, to the rear axis of the jaw forming the posterior border of the lip stripe. The posterior border of the orbits along the entire flanks to the base of the tail, lower mandible, throat, upper chest, forelimbs and dorsal surface of hind limbs brownish black. There is a single light brown blotch on the mid upper surface of the upper forearms and tibia. Two short longitudinal cream stripes on the posterior throat. The dark brownish black of the anterior chest gradually breaks up into blotches and spots to become cream posteriorly across the abdomen, vent and onto the tail. Cream spots and blotches break up the dark brown ventral surface of the thighs and tibia.

Condition of type series: All three specimens appear well preserved and are in good general condition. Each specimen has a longitudinal midventral incision, but are otherwise complete.

Variation: Variation of meristic and mensural characters in the type series of J. otai sp. nov. are summarized in Table 1. Due to the small sample size of the type series, conclusions on sexual dimorphism can not be reliably made, however the difference of male proportions relative to females in this series are consistent with known sexual dimorphism in several other species of Japalura –– longer hind leg, foot and tail length, and colouration differences. The tail base of the females are not swollen. It should at this point be mentioned that the holotype possess a colour pattern referred to in this paper as a “bicolour morph” (see Discussion section for further details). The two female paratypes considerably differ from the male holotype in colouration. Neither females possess the contrasting bicolouration of the holotype, they are instead primarily uniform brown dorsally. The spines of the posterior temporal region, enlarged dorsolateral and medial scale rows and dorsal “V” ridges are pale grey. Posterior three “V” rides of ZSI 25215 are bordered posteriorly by a thin dark brown line. One or two pale stripes with dark brown borders extend from the lower eyelids. The posterior oblique line is the more vivid and extends to the juncture of the upper and lower mandibles. The anterior stripe, if present extends as far as the lower edge of the orbit (figure 3). There is a light brown patch on the dorsal surface of the upper and lower forearm, elbow and tibia. Throat and chest is light brown broken by faded grey blotches over the abdomen and on ventral surface of thighs, tibia and feet. On one paratype (ZSI 25215) its nasal is separated from rostral by two scales (both sides), on the right side it is narrowly in contact with second SL only but not in contact with SL on the left side. On the second paratype (ZSI 25216) the nasal is separated from the rostral by two scales and on the left side separated from the second SL by one scale.

Distribution: The new species is known only from the type locality, Sairep, Lunglei District, central Mizoram, northeast India. Online resources provide for Sairep the GPS co-ordinates 22°49'N, 92°49'E, and altitude 1365 m asl. This species is likely to be found more widespread in Mizoram however currently very few herpetological surveys have been carried out in this state. Records of J. planidorsata from Myanmar may prove to be representative of J. otai sp. nov. which would result in its range extending east to the Chin Hills of western Myanmar (see Discussion below).

Etymology: The specific epithet is a noun in genitive case formed from the personal name Hidetoshi Ota of the Tropical Biosphere Research Center, University of the Ryukyus, Japan. His comprehensive work and taxonomic revisions of Japalura species have immensely contributed to our current knowledge of this genus.

Comparison: Japalura otai sp. nov. is most similar to J. planidorsata Jerdon, 1870 and J. sagittifera Smith, 1940 . From J. planidorsata (in brackets), it can be distinguished based on the following characters: fewer MD, 45–47 (vs. 52–61), more 4FinLam 17 (vs. 15–16) and 4ToeLam 21–22 (vs. 17–20), spines of the temporal region are primarily dorsoventrally flattened and posteriorly pointing (vs. mostly conical, oriented at approximately 90° angle to the skin surface), nasal narrowly in contact with second SL or separated by one scale row, separated from the rostral by one or two scales (vs. nasal in contact with first SL and separated from the rostral by one scale), female adult size larger, SVL to 58.7 mm (vs. to 49.1–52.7, N=3 (inc. syntype), elsewhere largest published records are 50 mm (Smith 1935)), the male holotype SVL 46.6 mm (vs. male syntype SVL 35.9 mm, elsewhere reported as 33–38 mm (Das, 2008)), longer and wider head, HW/SVL 26.2–28.2% (vs. 21.4–23.3%) and HW/HL 77–82.6% (vs. 70.6–72.2%), shorter trunk length, TrL/SVL 42.9– 46.6% (vs. 48.4–52.8%), longer tail, TailL/SVL 160.5–162.8% (vs. 148.2–148.6%), and longer crus and hind foot lengths, CrusL/SVL 27.4% (vs. 25.2–25.7%) and FootL/SVL 37.1–39.5% (vs. 32.7–33.2%). Das (2008) and Manthey (in prep.) include perhaps the only published photographs of an adult male J. planidorsata which differs from the male J. otai sp. nov. holotype most notably by possessing an orange/red gular region, represented as a small grey patch on the syntype (vs. jet black in J. otai sp. nov.). Additionally the male syntype of J. planidorsata has a wide white lip stripe that extends to above the shoulder also evident from male photographs in Das (2008) (vs. white lip stripe terminates at the rear axis of the jaw in J. otai sp. nov.).

From J. sagittifera (in parenthesis) it can be distinguished by having a greater number of SL, 10–11 (vs. 7–8) and IL, 9–12 (vs. 7–8), fewer MD, 45–47 (vs. 53–58) and fewer 4ToeLam 21–22 (vs. 25–27). Male colouration (in alcohol): dorsal surfaces of arms and legs and lateral surfaces of the head and body, dark brownish black (vs. light blue), ventral colouration of the male, solid brownish black on the throat and anterior chest, breaking up posteriorly into blotches and spots on an otherwise light cream background (vs. males with throat, chest and abdomen primarily creamy white, with or without sparse brown speckling on the anterior throat and abdomen).

From the species possessing a concealed tympanum, J. otai sp. nov. differs from J. andersoniana Annandale, 1905 , by its smaller adult size, SVL 46.4–58.7 mm (vs. to 75 mm), absence (vs. presence) of a nuchal crest and gular pouch, body subquadrangular (vs. moderately compressed laterally), lower number of 4ToeLam, 21–22 (vs. 28), and fewer MD, 45–47 (vs. 81). From J. variegata Boulenger, 1853 , by its smaller adult size, SVL 46.4–58.7 mm (vs. 59.6–95.4 Ota (1989c), to 110 mm (Smith 1935)), absence (vs. presence) of a raised dorsal and nuchal crest and gular pouch and absence (vs. presence) of a wide lateral white stripe in males. From J. hamptoni Smith, 1935 , J. yunnanensis Anderson, 1878 , J. flaviceps Barbour & Dunn, 1919 , and J. splendida Barbour & Dunn, 1919 , by its smaller adult size, SVL <58.7 mm (vs. to 77.2 mm, 75 mm, 86 mm, and 89.8 mm respectively) and absence (vs. presence) of a light lateral stripe and gular pouch, and further from J. hamptoni by absence (vs. presence) of a gular pouch and shorter head length, HW/HL 77– 82.6% (vs. approximately 66.7 %). From J. fasciata Mertens, 1926 , by smaller adult size, SVL to 58.7 mm (vs. to 71 mm), absence (vs. presence) of a nuchal crest and wide light transverse band on the body, and higher number of MD, 45–47 (vs. 35–38). From J. micangshanensis Song, 1987 , and J. zhaoermii Gao & Huo, 2002 , by absence (vs. presence) of a wide yellow/white longitudinal stripe and raised nuchal and dorsal crest in males, and male body subquadrangular (vs. moderately compressed), further from J. micangshanensis by having a longer hind limb length, reaching between the eye and snout (vs. to the neck) and from J. zhaoermii by absence (vs. presence) of a prominent green gular pouch in males and smaller adult size, SVL to 58.7 mm (vs. to 85 mm). From J. batangensis Li, 2001 , by absence (vs. presence) of a wide yellow longitudinal stripe and male body subquadrangular (vs. moderately compressed). J. otai sp. nov. differs from J. chapaensis Bourret, 1937 in having, fewer 4ToeLam, 21–22 (vs. 28–30), more MD, 45–47 (vs. 35–37), SL 10–11 (vs. 7– 8) and IL, 9–12 (vs. 7).

From the east Asian insular species, it differs from J. brevipes Gressit, 1936 , by having longer hind limbs, reaching between the eye and snout (vs. from the hidden tympanum to the posterior edge of the eye), a considerably shorter tail, TailL/SVL 160.5–187.5% (vs. 241.7–268.1%) and a greater number of SL, 10–11, (vs. 7–9). From J. luei Ota, Chen & Shang, 1998 , and J. makii Ota, 1989 c, in body shape, primarily subquadrangular (vs. moderately compressed), smaller adult size, males 46.6 mm, females 52.2–58.7 mm (vs. males 65.2–74.5 mm, females 68.2 mm and males 63–78.8 mm, females 60.6–71.6 mm respectively), fewer 4ToeLam, 21–22 (vs. 24–28 and 28–30, respectively) and absence (vs. presence) of a nuchal crest. From J.

polygonata (Hallowell, 1860 “1861”) and J. swinhonis Günther, 1864 , by absence (vs. presence) of a light lateral stripe and nuchal crest, body subquadrangular in cross section (vs. moderately compressed) and smaller adult size of the male, 46.6 mm (vs. males 50.3–80.2 mm and 58.1–82.7 mm respectively). The remaining species of Japalura ; J. dasi (Shah & Kästle, 2002) , J. dymondi ( Boulenger, 1906) , J. grahami ( Stejneger, 1924) , J. kaulbacki Smith, 1937 , J. kumaoensis ( Annandale, 1907) , J. major ( Jerdon 1870) , J. tricarinata ( Blyth, 1853) , and J. varcoae ( Boulenger, 1918) can be distinguished by possessing an exposed tympanum.

Figures

FIGURE 1. Japalura otai sp. nov., male (holotype ZSI 25217); (A) dorsal view, (B) ventral view.

FIGURE 2. J. otai sp. nov., male (holotype ZSI 25217); (A) profile view, (B) dorsal view of head, J. sagittifera, male (lectotype BMNH 1946.8.13.97); (C) profile view, (D) dorsal view of head. Images not to scale.

FIGURE 3. (A) A direct comparison between the head proportions and profile shape of two similarly sized adult specimens; a female Japalura otai sp. nov. (paratype ZSI 25215) SVL 52.2 mm (top) and a female J. planidorsata (ZSI 16024) SVL 52.7 mm (bottom), (B) head view of the same female J. otai sp. nov., (C) head view of the same female J. planidorsata. Images (B) and (C) are not to scale.