Nevada Fish & Wildlife Office
Pacific Southwest Region

Ash Meadows Speckled Dace
( Rhinichthys osculus nevadensis )

Ash Meadows Speckled Dace
Class: Actinopterygii
Order: Cypriniformes
Family: Cyprinidae
Genus: Rhinichthys
Species: osculus
Subspecies: nevadensis
Max Length: 8 centimeters
Reproduction: Spawns in early spring and again in late summer
Feed: Eats various small aquatic animals
Habitat: Spring/Spring Brook

Official Status:


Life History:

Originally included with the Amargosa speckled dace group in 1893, this subspecies is now referred to as the Ash Meadows speckled dace since it occurs only in the Ash Meadows area of the Amargosa River Basin in southern Nye County following extinction of speckled dace populations now considered to have been a separate species, Rhinichthys deaconi, in the Las Vegas area. Although previously known from at least ten springs and outflows in the Ash Meadows National Wildlife Refuge, by 1985 this rare fish was present in only three spring systems. It prefers fast-moving outflows and is omnivorous, feeding primarily on insects and algae. Like other Ash Meadows fishes, it is threatened by habitat modifications and introduction of non-native species such as bullfrogs, crayfish, largemouth bass, and snails.

Distribution and Habitat:

The Ash Meadows Speckled Dace is a non-migratory fish which typically lives in warm springs and their outflows.


Water development activities (e.g., water diversion, excessive pumping) that eliminated or degraded habitat. Formerly threatened by agricultural and residential development.

Actions / Current Information:

  • Initiation of 5-Year Reviews of 58 Species in California, Nevada, Arizona, and Utah; Availability of Completed 5-Year Reviews in California and Nevada
  • Determination of End. Status & Crit. Hab for Two Fish Species; Ash Meadows, NV; 48 FR 40178-40186
  • Endangered Status & Critical Habitat for Ash Meadows Amargosa Pupfish & Ash Meadows Speckled Dace; Emergency Rule & Proposed Rule; 48 FR 608-625
  • Review of Vertebrate Wildlife for Listing as End. or Thr. Species
  • Emergency Determination of Endangered Status for Two Ash Meadows, NV, Fish Species
    Last updated: April 16, 2014