Pacifastacus nigrescens   (Stimpson)

Sooty Grayfish
(Pacifastacus nigrescens)

syn. -


USA: Alameda County, Santa Clara County / California

local name: -

size: (?)

extinction date: ca. 1900

The Sooty Grayfish was endemic to the creeks surrounding the San Francisco Bay area.

The species was once very common, but died out in the early 19. century, after two species, the Signal Crayfish (Pacifastacus leniusculus (Dana)) and the Red Swamp Crayfish (Procambarus clarkii (Girard)), were introduced to its biotope.


- Larry L Eng; Robert A. Daniels: Life History, Distribution, and Status of Pacifastacus fortis (Decapoda: Astacidae). Calif. Fish and Game 68(4): 197-212. 1982