Anilios Gray, 1845

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 : 61

Anilios Gray, 1845

Type species. Anilios australis Gray, 1845

Species content. Anilios affinis , An. ammodytes , An. aspina , An. australis , An. batillus , An. bicolor , An. bituberculatus , An. broomi , An. centralis , An. chamodracaena , An. diversus , An. endoterus , An. erycinus , An. ganei , An. grypus , An. guentheri , An. hamatus , An. howi , An. kimberleyensis , An. leptosomus , An. leucoproctus , An. ligatus , An. longissimus , An. margaretae , An. micrommus , An. minimus , An. nema , An. nigrescens , An. nigricaudus , An. nigroterminatus , An. pilbarensis , An. pinguis , An. polygrammicus , An. proximus , An. robertsi , An. silvia , An. splendidus , An. tovelli , An. troglodytes , An. unguirostris , An. waitii , An. wiedii , An. yampiensis , and An. yirrikalae .

Diagnosis. Anilios can be distinguished from all other typhlopoids by a protrusible hemipenis, retrocloacal sacs, absence of frontorostral, and paired prefrontals. Small- to large-sized (total length 60–750 mm), stout to slender-bodied (length/width ratio 20–122) snakes with 16–24 scale rows (usually without reduction), 263–750 total middorsals, short to long tail (0.9–7.7% total length) with 8–36 subcaudals (length/width ratio 0.8–4.4), and apical spine small. Dorsal head profile rounded or tapered, lateral head profile rounded to acutely pointed, narrow to broad rostral (0.23–0.75 head width), inferior nasal suture in contact with first or second supralabial or preocular, preocular in contact with second and third supralabials, eye moderate with distinct pupil or reduced to eyespot, T- III SIP, and postoculars 1–4. Lateral tongue papillae present; left lung absent, tracheal lung multicameral (with 18–48 chambers), cardiac lung multicameral (with 1–10 chambers) or paucicameral (with 2–10 pockets) and right lung multicameral (with 1–15 chambers), paucicameral (with 2–13 pockets) or unicameral; testes usually unsegmented; hemipenis protrusible (retracted organ with 0–10 coils), retrocloacal sacs present; and rectal caecum small to large (1.0–7.7% SVL). Coloration usually light brown, brown, reddish-brown, purplish-brown or black above and cream, white or yellow below but some species are pink (pigmentless).

Phylogenetic definition. Includes the MRCA of Anilios australis and An. polygrammicus and all descendants thereof, and all species more closely related to An. australis than to the type species of the 16 other typhlopid genera listed here.

Etymology. Name refers to the fossorial habits of most species, from the Greek for without sun (an-helios).

Distribution. Australia (with several species extending into southern New Guinea).

Remarks. The Australian members of this genus have been previously referred to as Austrotyphlops ( Wallach 2006) , but this name is a junior synonym of Anilios ( Wallach & Glaw, 2009; Savage & Boundy 2012). Species richness in this group is known to be underestimated by a large amount, based on molecular dataset examining 27 nominal species in Ramphotyphlops finding at least 54 potential species ( Marin et al. 2013). Note that Hedges et al. (2014) did not recognize the clearly valid species An. nigricaudus (Wallach et al. 2014; Table 1). Those authors separated An. polygrammicus into a separate, monotypic genus Sundatyphlops, forming the sister group of Anilios . However, Sundatyphlops cannot be unambiguously diagnosed morphologically (Table 2, 8), and this naming scheme does not increase the phylogenetic informativeness of the taxonomy due to monotypy. Thus, we formally propose to synonymize Sundatyphlops with Anilios . Visceral anatomy does support the conclusion of Hedges et al. (2014) that Australo-Papuan populations of An. " polygrammicus " are actually a separate species, An. torresianus ( Table 9).