Fork length: the straight-line distance from the tip of the head (snout) to the rear center edge of the tail (caudal fin).

Total length: the straight-line distance from the tip of the snout to the tip of the tail (caudal fin), excluding any caudal filament, while the fish is lying on its side. The mouth of the fish may be closed and/or the tail may be squeezed together to give the greatest overall measurement.

Carapace length: The carapace is measured beginning at the forward edge between the rostral horns, excluding any soft tissue, and proceeding along the middle to the rear edge of the carapace.