Caitlin Bloomer found a huge crayfish in Kentucky. Her discovery started a search for bigger ones. Scientists checked museum collections. They listed 20 large crayfish from 18 different kinds.
The largest was a Tennessee bottlebrush crayfish at West Liberty University. Its body measured 86.6 millimeters, about 3.4 inches. This measurement did not include its tail, claws, or feelers. Bloomer's crayfish also made the list.
The biggest crayfish generally measured around 80 millimeters. Scientists found no clear link between size and location, oxygen, or living conditions. Their hard outer shells or muscles may limit their growth instead. This is still only a possible explanation. Scientists need to study it more.
