Cambarus

Cambarus is a large and diverse genus of crayfish from the United States and Canada. The adults range in size from about up to approximately .

== Description == The genus Cambarus is the second largest freshwater crayfish genus inhabiting the Northern Hemisphere, with only sixty fewer species than the genus Procambarus. Though Cambarus are varied across species, the two terminal elements that make up the male form I gonopod form ninety degree angles with the central appendage, allowing for their identification. Unlike the genus Procambarus whose first pleopod tends to have three processes at the tip, Cambarus has only one or two. Cambarus reach carapace lengths in their first year, while average adult carapace length ranges from . The name Cambarus comes from an alteration of Latin cammarus, meaning "lobster".