Researchers find record giant crayfish and investigate freshwater crustacean growth limits

ScienceDaily reported that researchers conducting a nationwide survey for giant crayfish discovered a record-breaking specimen in Tennessee. The large freshwater crustacean, nicknamed Crawzilla, was pulled from the mud by researcher Caitlin Bloomer during a biological survey. [1]

According to ScienceDaily, the discovery triggered a broader investigation into how large North American freshwater creatures can grow. Scientists observed that North American crayfish appear to hit a strict biological size limit. [1]

ScienceDaily reported that researchers hypothesize this growth constraint is caused by physical limitations related to the muscles or protective exoskeletons of the animals. Exoskeletons are rigid external covers that protect invertebrate bodies and must be shed for growth. [1]

Lacunicambarus is a genus of burrowing crayfishes in the family Cambaridae, comprising 12 described species located east of the Continental Divide in North America. The genus was recognized in 2018 after genetic analyses revealed that combining the subgenera Lacunicambarus and Tubericambarus formed a single distinct monophyletic group. [2]