Hemidactylus hajarensis, Carranza & Arnold, 2012

Carranza, Salvador & Arnold, Edwin Nicholas, 2012, 3378, Zootaxa 3378, pp. 1-95 : 30-34

Hemidactylus hajarensis sp. nov.

( Figs. 2, 5B, 6, 9B–D, 12–13; Table 1; Appendix I; Appendix IIIB)

MorphoBank M94393 – M94415 M94459 – M94465 M94515 – M94542 M94558 – M94586 M94630 – M94643 M94649 – M94664 M94666 – M94684 M94700 – M94721 M99874 – M99917 M99921 – M99937 M99954 – M99993

Hemidactylus persicus Arnold, 1986: 419 ; Leviton, Anderson, Adler and Minton, 1992: 38 (part.); van der Kooij, 2000: 112 (part.); Carranza and Arnold, 2006: 536; Sindaco and Jeremcenko, 2008: 115 (part.).

Holotype

BMNH2008.714 , male from Wadi Bani Khalid , 647 m, Eastern Hajar (North Oman), 22.61609’ N 59.09371 ’E WGS84, collected in May 2011 by S. Carranza, E. Gómez-Díaz and F. Amat (MorphoBank M99903 – M99917 ; Fig. 12D). Paratypes: ONHM3706 , male, same collecting data as Holotype (MorphoBank M99885 – M99893 ); IBES7335 , male, same collecting data as Holotype (MorphoBank M99894 – M99902 ; Fig. 11D); IBES7336 , female, same collecting data as Holotype (MorphoBank M99969 – M99976 ).

Other material examined

Eighteen vouchers listed in Appendix I under H. hajarensis sp. nov. and not mentioned above. Specimens CAS 227612, CAS 227614, BMNH 2008.705 (juvenile) and samples JS65, JS81, JS98 JS99, S7321, and S6061 were included in the molecular analyses only (Table 1).

Diagnosis

A medium-sized Hemidactylus with a maximum recorded SVL of 66.9 mm; with a mean of 14.2 (13–15) longitudinal rows of enlarged dorsal tubercles at mid-body; adhesive pads fairly broad, in adults maximum width of pad on the fourth toe about 0.4–0.5 of its length; lamellae under the 1 st toe of pes mean 8.0 (7–9); lamellae under the 4 th toe of pes mean 12.1 (11–14); preanal pores mean 5.5 (4–6); expanded subcaudal scales extending proximally as far as the second or third whorl after the vent and starting just after the hemipenial bulge in males; dorsum grey-buff with irregular small spots; a dark stripe from the nostril, through the eye, on to cheek above ear and often on to neck; tail with small irregular dark blotches basally and numerous transverse dark bands more distally, the total number being around 17. Underside of tail pale but large subcaudals may be suffused with grey formed by dark chromatophores that increase in intensity distally; underside of toe pads also grey.

Hemidactylus hajarensis is generally similar to H. persicus in the number of its moderately-sized dorsal tubercles across mid-body, and large adhesive pads on toes but differs from it in its reduced number of preanal pores in males (mean 5.5, 4–6, compared with mean 9.2, 8–11). Hemidactylus hajarensis differs from H. luqueorum sp. nov. in its smaller size (SVL mean 54 mm, max. 66.9 mm, compared with mean. 76.8 mm, max. 88 mm), and in having fewer lamellae under the 1 st toe of pes (mean 8.0, 7–9, compared with mean 10.3, 10–11), and under the 4 th toe of pes (mean 12.1, 11–14, compared with mean 13.6, 13–14)

Etymology

The species epithet “ hajarensis ” is an adjective that refers to the mountain range where the species is found, the Hajar Mountains.

Genetic and phylogeographic remarks

Hemidactylus hajarensis is monophyletic in the phylogenetic analyses of Dataset 1 ( Fig. 5B) and Dataset 3 (Appendix IIIB). In both phylogenetic trees it forms a clade together with H. persicus and H. luqueorum sp. nov., although bootstrap support and pp values are very low (see Fig. 5 and Appendix III). According to the results of the dating analysis inferred with Dataset 2, these three species split about 12.6 mya (95% HPD: 7.7–17.9). According to Fig. 5 and Appendix III, H. hajarensis is more closely related to H. luqueorum ( Fig. 5B, Appendix IIIB), from which it split approximately 9.6 mya (95% HPD: 5.7–13.8). The level of genetic variability within H. hajarensis is very high, 6.1% in the cytb and 2.6% in the 12S. As shown in Fig. 5B and Appendix IIIB, H. hajarensis consists of two very well differentiated and well-supported clades, B1 and B2. The uncorrected genetic distances between these two clades are 10.5% in the cytb and 5% in the 12S. As shown in Fig. 2, the geographical limits between clades B1 and B2 are not very clear, being clade B1 present in the Jebel Akhdar and in the coastal areas close to Muscat (Wadi Mayh, Jebel Abu Daud and a wadi North of Qurayyat), while clade B2 seems restricted to the Eastern Hajars. According to the calibrations, clades B1 and B2 split approximately 4.7 mya (95% HPD: 2.6–7.0). The uncorrected genetic distances between H. hajarensis and H. luqueorum are 15.6% in the cytb and 6.9% in the 12S; and between H. hajarensis and H. persicus 15.1% in the cytb and 10.7% in the 12S. The results of the nuclear networks presented in Fig 6 and a network analysis including all specimens from Dataset 1 (data not shown) indicate that all alleles of H. hajarensis for all three independent loci analyzed (c -mos, mc1r and rag2) are private (not shared with any other species included in the present analyses). It is also interesting to notice that, although clades B1 and B2 share alleles of the c -mos gene, specimens of these two clades do not share a single allele of the mc1r and rag2 nuclear genes. The high genetic differentiation between clades B1 and B2 of H. hajarensis suggests long separation of the two units. However, the absence of clear morphological differences between these two clades and the relatively low number of available vouchers to carry out a thorough morphological analysis prevents us from taking any taxonomic decisions at present. Future studies should clarify the taxonomic status of these two clades (work in progress).

Distribution

The species is widespread in the mountains of North Oman from the Jebel Akhdar to the East. Despite intensive surveys across the Hajar Mountain range, it has never been found to the West of the Jebel Akhdar, in the Western Hajars or in the Musandam Peninsula. Several localities exist for the coastal wadis near Muscat and the Eastern Hajars, from Jebel Al Abyad in the West to Jebel Qahwan in the extreme East. Across its distribution range it has been recorded from almost sea level (22 m in Wadi Mayh) up to 1683 m in a locality 9 km North of Al Chayan (Table 1).

Habits

Hemidactylus hajarensis has been found at sides of wadis low on rocks that were interspersed and sometimes partly overhung with vegetation. The species was also sometimes seen on gravel floors of wadis ( Fig. 13). Strictly nocturnal, it has never been recorded during the day. H. hajarensis moves quickly and is very agile, fleeing to a nearby refuge seconds after being spotted. In Wadi Tiwi and Wadi Hebaheba, H. hajarensis occurs also low on rocks. As H. luqueorum , it losses the skin very easily when being handled and sometimes specimens have scars of regenerated skin on the back, probably as a results of fights with conspecifics or attacks from predators ( Fig. 12D). This species has never been found in sympatry with H. luqueorum , however, it shares habitat with Asaccus platyrhynchus and Ptyodactylus hasselquistii .

Description

Head and body markedly depressed. Head breadth variable and neck well defined. Head length about 24–31% of SVL (mean males 28%, mean females 27%), head width 65–85% of head length (mean males 71%, mean females 72%), and head height 36–55% of head length (mean males and females 42%). Adhesive pads fairly broad; in adults maximum width of pad on fourth hind toe about 0.4–0.5 of its length.

Nostril between rostral, supranasal and two superposed postnasals, with the first supralabial scale usually also entering narrowly into its border. Usually one scale separating supranasals on midline. About 14–18 scales in a straight line from postnasal to edge of orbit. Small conical tubercles scattered in orbital area, crown of head and temporal area above the level of ear opening and immediately in front of the upper part of this. Ear opening with its longest axis running upwards and backwards, smooth-edged, usually about half or more of eye diameter. Supralabial scales mean 10.7 (9–12), infralabials mean 8.8 (7–10). Mental scale broadly triangular posteriorly bordered by two large postmentals making contact behind it, a second pair of more lateral postmentals also present, the postmentals contacting the first and second supralabials; second and more posterior lower labials bordered by more irregular and smaller enlarged scales. Gulars fine.

Enlarged tubercles present on back, arranged in 14.2 (mean) (13–15) longitudinal rows at mid-body, which also form backwardly directed oblique rows from near midline to flank, and 16–18 in a paravertebral row from the level of the axilla to that of the groin, where they are separated by spaces of about their own length. Enlarged tubercles strongly keeled and trihedral but becoming smaller and more conical on flanks. Ventrals small, but larger than dorsals and more imbricate, about 34–43 in a transverse row at mid body between lateral folds. Males with 4–6 preanal pores (mean 5.5) separated by one or two scales giving a formula of 2+2 or 3+3. Scales on upper forelimb small and imbricate, interspersed with enlarged tubercles on distal section. Scales on front of thigh and beneath hind leg about same size as belly scales and imbricate, enlarged tubercles present on upper surface of both femur and tibia. Lamellae under the toes of pes: 1 st toe mean 8.0 (7–9), 4 th toe mean 12.1 (11–14).

Tail relatively slender; between eight and six enlarged, keeled and pointed tubercles on each whorl on tail base, dropping to four from about 4–10 th whorl after vent. Tubercles about one third the length of basal whorls, becoming smaller and placed more posteriorly on whorls distally. Subcaudal scales enlarged and broad, extending proximally as far as the second or third whorl after the vent and the starting just after the hemipenial bulge in males.

In spirit pale grey-buff; a dark stripe from the nostril, through the eye, on to cheek above ear and often on to neck; body with irregular small spots; some tubercles on forebody and vertebral area have opaque white coloring on one side and dark coloring on the other. Belly pale but there may be a very fine slight stipple at the sides, the dark punctuate spots being much smaller than the scales. Tail with small irregular dark blotches basally and numerous irregular dark bands more distally, the total number being around 17. Underside of tail pale but large subcaudals may be suffused in some places with grey formed by dark chromatophores that increase in intensity distally. Underside of toe pads also grey. In life, animals from many localities have dark blotches or bars on the upper surface that are suffused yellow-orange.

Distinctive features of Holotype

Male, 59.8 mm SVL; tail missing from the base. Supralabial scales 10/10; infralabials 9/9; 14 rows of enlarged tubercles at mid-back; 6 (3+3) preanal pores; lamellae under the 1 st toe of pes 8/8, 4 th toe of pes 12/12.