Among the Macrura we are acquainted with the same earliest form principally in several Shrimps and Prawns, such as Crangon (Du.    From Wordnik.com.  [Facts and Arguments for Darwin] Reference

A fresh catch of brown shrimp, Crangon Crangon.    From Wordnik.com.  [WN.com - Business News] Reference

Crangon.    From Wordnik.com.  [Facts and Arguments for Darwin] Reference