Eristicophis is a monotypic genus of venomous snakes in the true viper family (Viperidae). Its single recognized species, Eristicophis macmahoni, is commonly called McMahon's viper, the Asian sand viper, the leaf-nosed viper, or the whiskered viper. The genus is notable for its specialization to arid, sandy environments and for having no currently recognized subspecies.

Identification and characteristics

McMahon's viper is a relatively small, stout-bodied viper adapted for life on loose desert sand. Typical features reported for the species include a distinct triangular head, keeled dorsal scales, and coloration that helps it blend with sandy and rocky substrates. The common name "leaf-nosed" refers to structures around the snout that aid in sensing or disturbing sand. As with other vipers, it is venomous, using a hinged-fang delivery system to subdue prey.

Distribution and habitat

The species occurs in desert and semi-desert zones near the borders of Iran, Pakistan and Afghanistan. It is associated with sandy plains, dunes and stony desert flats where loose substrate facilitates its ambush and sand‑swimming behaviors. Regional references and field studies often link its range to specific border regions and desert tracts; general overviews can be found via genus and species treatments such as genus accounts and the species page above.

Behavior, diet and reproduction

  • Behavior: Primarily nocturnal or crepuscular in hot months, with ambush hunting and partial sand-burying common.
  • Diet: Small mammals, lizards and other vertebrate prey typical of desert vipers.
  • Reproduction: Like many vipers, it is believed to be live-bearing (ovoviviparous), though detailed reproductive studies are limited.

Taxonomy, research and conservation

Eristicophis is placed among Old World vipers (subfamily Viperinae). The genus and its single species have attracted interest because of their specialized desert adaptations and restricted range near the frontiers of Iran (Iran), Pakistan (Pakistan) and Afghanistan (Afghanistan). Scientific knowledge remains incomplete: field observations are sporadic, and population assessments are limited. Potential threats include habitat disturbance, persecution, and collection for the pet trade. Conservation status for the species is variable in different sources, and further survey work would clarify its risk factors.

For additional background on its desert environment see regional desert resources (desert habitats) and consult taxonomic summaries for viper genera for comparative context.