Xerotyphlops Hedges, Marion, Lipp, Marin & Vidal, 2014

Pyron, Robert Alexander & Wallach, Van, 2014, Systematics of the blindsnakes (Serpentes: Scolecophidia: Typhlopoidea) based on molecular and morphological evidence, Zootaxa 3829 (1), pp. 1-81 : 54

Xerotyphlops Hedges, Marion, Lipp, Marin & Vidal, 2014

Type species. Typhlops vermicularis Merrem, 1820

Species content. Xerotyphlops etheridgei, Xer. socotranus, Xer. vermicularis , and Xer. wilsoni (?).

Diagnosis. Xerotyphlops can be distinguished from all other typhlopoids by the combination of the following characters: small- to moderate-sized (total length 92–405 mm), stout- to moderate-bodied (length/width ratio 34–56) snakes with 20–30 scale rows (usually with reduction), 346–435 total middorsals, short to moderate tail (1.1–3.1% total length) with 7–13 subcaudals (length/width ratio 1.0–1.5), and apical spine. Dorsal and lateral head profiles bluntly rounded, narrow rostral (0.27–0.41 head width), inferior nasal suture in contact with second supralabial, preocular in contact with second and third supralabials, eye moderate with distinct pupil, T-III or T-V SIP, and postoculars 2–3. Lateral tongue papillae present; left lung absent, tracheal, cardiac and right lungs multicameral (with 22–29 + 5–9 + 2–9 chambers, respectively); testes segmented; hemipenis eversible, lacking retrocloacal sacs; and rectal caecum moderate (1.4–2.2% SVL).

Phylogenetic definition. Includes the MRCA of Xerotyphlops vermicularis and Xer. socotranus and all descendants thereof, and all species more closely related to Xer. vermicularis than to the type species of the 15 other typhlopid genera listed here.

Etymology. Named after the desert (xeric) habitats of the species.

Distribution. The type species ( Xerotyphlops vermicularis ) occurs from southeastern Europe through the Middle East. The other three species are more localized, with Xer. etheridgei in Mauritania, Xer. socotranus on Socotra, and Xer. wilsoni in southwestern Iran.

Remarks. Assignment of Xerotyphlops wilsoni is tentative, as it is only known from the lost holotype, which has not been examined, though other putative specimens have been sighted near the type locality (B. Safaei, pers. comm.). Little morphological data is known for this species from the brief description (Table 2). This group likely contains additional cryptic species ( Kornilios et al. 2012).