Definitions

In shrimps, distance from the posterior margin of orbit to midcaudodorsal margin of carapace; in crayfishes, distance from tip of rostrum to midcaudodorsal margin of carapace (see Fig. 14). [Hobbs and Jass, 1988]
In shrimps, the distance from the posterior margin of the orbit to the mid-caudodorsal margin of the carapace; in crayfishes, the distance from the tip of the rostrum to the mid-caudodorsal margin of the carapace. [Hobbs, Hobbs, and Daniel 1977]