Aaptosyax grypus Rainboth, 1991

Description


Well-developed adipose eye-lid, covering most of eye except pupil in large adults, less extensive in juveniles; presence of a large symphyseal knob in lower jaw fitting in a median notch in upper jaw (Ref. 43281).

Taxonomic Hierarchy


Kingdom: Animalia

Phylum: Chordata

Class: Teleostei

Order: Cypriniformes

Family: Cyprinidae

Genus: Aaptosyax

Species: Aaptosyax grypus Rainboth, 1991

Climate Zone


  • Tropical
  • Location


  • Asia: Mekong River.
  • Biology


    Inhabits mainstreams of middle reaches in deep rocky rapids. Juveniles occur in tributaries (Ref. 58784). A large fast-swimming predator, feeding on fish of the middle and the upper water levels. Although most common along the Thai-Lao border at the mouth of the Mun River, its numbers have drastically decreased in recent years. This is perhaps due to dam construction or excessive gill netting, to which active pursuit predators, like this species, are particularly vulnerable (Ref. 12693). Undertakes upstream migration at the same time as Probarbus sp. in December-February (Ref. 37770) which may be related to spawning activity (Ref. 9497). Attains over 30 kg (Ref. 9497).

    Habitat


    pelagic

    Conservation Status


    Critically Endangered

    Threat to Humans


    Harmless