Leptotyphlopinae (Hedges, 2008)

Adalsteinsson, Solny A., Branch, William R., Trape, Sébastien, Vitt, Laurie J. & Hedges, S. Blair, 2009, Molecular phylogeny, classification, and biogeography of snakes of the Family Leptotyphlopidae (Reptilia, Squamata), Zootaxa 2244, pp. 1-50 : 25-27

Subfamily Leptotyphlopinae

Type genus. Leptotyphlops Fitzinger, 1843: 24 .

Diagnosis. Members of Leptotyphlopinae usually have long, thin tails, with high subcaudal counts: relative tail length is 4.1–18.9 % total length versus 2.1–11.5% in the Epictinae , tail shape is 3.2–11.7 versus 1.3–6.1, and subcaudals number 12–58 versus 6–30 in the Epictinae (Table 2; Fig. 5). All leptotyphlopids possessing more than two supralabials, more than 14 midbody scale rows, stripes, and bold colors (e.g., reds and yellows) are in the Epictinae rather than this subfamily. The support for this group was 100% BP and 100% PP for the four-gene tree ( Fig. 3) and 100% BP and 100% PP for the nine-gene tree ( Fig. 4).

Content. Three tribes, four genera, and 54 species ( Table 1; Figs. 9–10).

Distribution. Leptotyphlopinae is distributed throughout Africa (north and south of the Sahara Desert) as well as on nearby islands (Bazaruto archipelago, Pemba, Manda, Lamu, and Socotra), the Arabian Peninsula, and in southwest Asia ( Turkey, Iran, Pakistan, and northwest India).

Remarks. We divide this subfamily into three tribes. Two are well-defined, include 51 of the 54 species, and correspond to the former longicaudus Group of " Leptotyphlops " on one hand (a primarily northeast Africa-Arabia clade) and the former nigricans , rostratus , and scutifrons groups of " Leptotyphlops " on the other hand (a primarily southern African clade). The remaining three species, corresponding to the former reticulatus Group of " Leptotyphlops ," are placed here in a third tribe (A primarily East African clade); no molecular data were available for this tribe. A few characters previously used to define species groups, such as the fusion of skull bones and of the frontal and rostral scales ( Broadley & Wallach 2007), show homoplasy among the genera of Leptotyphlopinae recognized here and therefore are excluded from diagnoses of taxa. Nonetheless combinations of those characters may still prove to be diagnostic for restricted clades of species. Hedges (2008) noted that Old World species of Leptotyphlops have a more pronounced sexual dimorphism in body size, averaging ~1.3 (total length of average adult female/total length of average adult male), compared with New World species (~1.1). However, data are available for only nine species of New World Epictinae and three species of Leptotyphlopinae ( Bailey 1946; Zug 1977; Thomas et al. 1985; Broadley 1996; Webb et al. 2000; Passos et al. 2005, 2006), and therefore more sampling is needed before this trend can be considered diagnostic of the two subfamilies.