Cambarus aculabrum

Cambarus aculabrum is a rare species of crayfish known by the common name Benton cave crayfish.[2] It is native to Arkansas in the United States, where it is known from only four locations.[2] It is a federally listed endangered species of the United States.[3]

Cambarus aculabrum
Conservation status
Critically Endangered  (IUCN 3.1)[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Crustacea
Class:	Malacostraca
Order:	Decapoda
Family:	Cambaridae
Genus:	Cambarus
Species:	C. aculabrum
Binomial name
Cambarus aculabrum Hobbs & Brown, 1987

This crayfish was first described to science as a new species in 1987. It is about 48 millimeters (1.8 inches) long. A troglobite, it lacks pigment, making it white in color, it and has only rudimentary eyes. It is genetically distinct from other species of cave crayfish.[3]

The crayfish lives at four caves in northern Arkansas, three in Benton County and one in Washington County. It is not considered an Arkansas endemic species because 58% of one of the Benton County cave zones is actually within the neighboring state of Missouri although it has not yet been found in Missouri.[2]

This crayfish feeds on organic matter washed into the cave from the surface, and on bat guano.[4] It is sometimes eaten by the banded sculpin (Cottus carolinae). Little else is known about its ecology.[2]

Threats to this species include direct mortality when they are trampled by cave explorers and trespassers. Gates have been put in place at the caves to protect them but vandalism is still a threat. Pollution of the groundwater in the caves was the main reason the animal was federally listed. Individuals are sometimes washed out of caves during floods, leading to mortality.[2]