Hemidactylus yerburii, Arnold, 1977

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

Hemidactylus yerburii and similar species

According to Anderson, 1895: 636, the types of Hemidactylus yerburii come from “Haithalhim and Laheh” although the types were registered at the British Museum as from Haithalhim ( BMNH 95.5.23.9) and Aden ( BMNH 95.5.23.8) (Appendix I). Specimens from the type localities or near the type localities are characterized by relatively small size (SVL mean 63.6 mm, max. 67.6 mm), high number of enlarged tubercles present on back, arranged in 16.7 (mean) (16–17) longitudinal rows at mid-body, a high number of preanal pores in males (mean 12.8, 10–15) in a V-shaped line in front of the vent and the enlarged laterally expanded subcaudal scales often do not begin until 3–6 (average 4.5) tail whorls after the vent .

According to Arnold (1980, 1986), there is a very marked geographical variation among specimens assigned to H. yerburii . For instance, the Northernmost populations assigned to H. yerburyii , which come from around an- Namas and Sabt Al Alaya in the Northern Asir Mountains ( Saudi Arabia) are like Southern Asir animals in having fewer femoral pores (9–11) than typical H. yerburyii and in the expanded subcadual scales beginning closer to the vent, being separated from it by 2–4 whorls (average 2.5), (pers. observ.). However, they are distinctive from typical H. yerburii in being large (up to 72 mm from snout to vent), and in having dorsal tubercles that are reduced in size and not obviously trihedral, at least on the mid-back. These animals may also sometimes have more dark transverse bars on the intact tail than typical H. yerburyii . The taxonomic status of these distinct Saudi Arabian populations of H. yerburii is under study.

Morphological variation of Yemeni populations formerly assigned to H. yerburii has been recently assessed using both morphological and molecular data by Busais and Joger (2011a,b). The results of these investigations led to the description of one new species: H. jumailiae , and one subspecies: H. yerburii montanus , endemic to the mountains of Southwest Yemen. Two other species of Hemidactylus that externally resemble H. yerburii but that are phylogenetically unrelated to it have also been described in the same work: H. shihraensis and H. saba . Before the studies by Busais and Joger (2011a,b), the only specimen of H. yerburii that had been included in a molecular phylogeny was a specimen from Najran, Saudi Arabia ( Carranza & Arnold 2006). According to the analysis by Carranza and Arnold (2006), H. yerburii branched outside the Arid clade, sister to H. mabouia . A closer examination of the mtDNA sequences revealed that the 12S mtDNA of H. yerburii was, in fact, from H. mabouia . The cytb sequence of H. yerburii from Carranza and Arnold (2006) was correct and it has been used in other studies ( Moravec et al. 2011).

Medium-sized Hemidactylus with numerous enlarged dorsal tubercles that occur in the Dhofar area of Southern Oman and neighboring East Yemen have been previously assigned to H. yerburyii . However, considerable geographic variation in the populations placed in this species has been noted including differences within Dhofar itself ( Arnold 1980, 1986). Morphology (Appendix I; Figs. 14–15, 17–18), phylogenetic analyses of Dataset 1 ( Fig. 5) and Dataset 3 (12S only; Appendix III), and nuclear networks of three independent loci (c -mos, mc1r and rag2) ( Fig. 7) indicate that two species are present in the Dhofar region in Southern Oman and neighboring East Yemen. Although they have been found in sympatry in one locality in East Yemen ( Fig. 2), these two species usually differ in habitat.