Argyrophis 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 : 53-54

Argyrophis Gray, 1845

Type species. Typhlops muelleri Schlegel, 1839

Species content. Argyrophis bothriorhynchus , Ar. diardii , Ar. fuscus , Ar. giadinhensis , Ar. hypsobothrius , Ar. klemmeri , Ar. koshunensis , Ar. muelleri , Ar. oatesii , Ar. roxaneae , Ar. siamensis , Ar. trangensis .

Diagnosis. Argyrophis can be distinguished from all other typhlopoids by the combination of the following characters: T-II, T-III, or T-V SIP and scale row reduction, and left lung present in Ar. diardii , Ar. muelleri , and Ar. siamensis . Small- to large-sized (total length 75–540 mm), stout- to slender-bodied (length/width ratio 24–71) snakes with 20–30 scale rows (with reduction), 246–402 total middorsals, short to moderate tail (1.0–3.6% total length) with 5–26 subcaudals (length/width ratio 0.4–2.0), and apical spine small or thorn-like. Dorsal and lateral head profiles rounded, moderate rostral (0.25–0.40 head width), preocular in contact with second and third supralabials, eye moderate with distinct pupil, and postoculars 2–3. Lateral tongue papillae present; vestigial left lung present, tracheal, cardiac and right lungs multicameral (with 23–38 + 3–10 + 2–12 foramina, respectively); testes unsegmented; hemipenis eversible, lacking retrocloacal sacs, and moderate rectal caecum (1.2–5.0% SVL). Coloration brown, reddish-brown, purplish-black or black dorsally, transiting to a lighter venter (beige, cream or white) or bicolored (with a sharp midlateral demarcation between dark dorsum and light venter), snout, labials, and chin sometimes light.

Phylogenetic definition. Includes the MRCA of Argyrophis diardii and Ar. muelleri and all descendants thereof, all species more closely related to Ar. muelleri than to the type species of the 15 other typhlopid genera listed here.

Etymology. Unclear. Many names erected by J.E. Gray were apparently chosen for euphony but lack any substantial etymology (A.M. Bauer, pers. comm.).

Distribution. Occurs in Southeast Asia, primarily Vietnam, Thailand, and West Malaysia.

Remarks. The species Argyrophis fuscus was considered Typhlopidae incertae sedis by Hahn (1980) and McDiarmid et al. (1999), who suspected the type locality of Java to be in error. The type (MNHN 1062) of Ar. fuscus has been examined and reveals a relationship to the Ar. diardii group (Table 2), so the locality may be correct. The species Ar. hypsobothrius is known only from a briefly described and now lost ZMH holotype destroyed in July 1943 (during WW II; fide Hallermann 1998), and Ar. koshunensis from Taiwan is also poorly known. However, these species are all clearly allied with Argyrophis on the basis of morphology (Table 2). Note that this genus is not included in our molecular phylogenetic analysis, but was analyzed by Hedges et al. (2014), who found weak support for a sister-group relationship between Argyrophis and Xerotyphlops . Those authors also included Indotyphlops leucomelas and I. tenuicollis in Asiatyphlops (= Argyrophis ), but those species seem to be allied with Indotyphlops on the basis of a T-III SIP, caudal spine reduced to nubbin, and invisible eye. They also included Ar. hypsobothrius in Indotyphlops , though it is likely allied with Argyrophis on the basis of head shield pits or grooves as in Ar. bothriorhynchus . As noted above, Argyrophis is the objective senior synonym for Asiatyphlops, as Ar. muelleri is the type species of both genera.