Morphology of the Zoeae Larvae of Brachyura (Crustacea, Decapoda) in Veracruz, Southwestern Gulf of Mexico

Abstract

Larval zoeae of Brachyura were collected from five coastal systems located in the State of Veracruz, southwestern Gulf of Mexico. Some morphological differences among the zoeae families have been determined. Morphological analysis consisted of the following determinations: presence of rostral spines, dorsal and lateral, on the carapace; number of setae of the exopod, endopod, and protopod of the antenna; number of processes; shape and size of the somites of the abdomen; and the presence and number of spines on the furcae and inner margin of thetelson. A total of 92839 zoeae of Brachyura were obtained, and 14 families were identified: Aethridae, Calappidae, Portunidae, Menippidae, Panopeidae, Gecarcinidae, Grapsidae, Sesarmidae, Varunidae, Inachidae, Epialtidae, Pinnotheridae, Ocypodidae, and Ucididae. Morphological differences between these families include: Epialtidae and Inachidae lack lateral spines; Pinnotheridae lacks spines on one side of the carapace,and there may be a wing shape on the fifth abdominal somite; the exopod of the antenna is short in Grapsidae and well-developed in Ucididae; the fourth abdominal somite is significantly expanded in Ocypodidae; the family Gecarcinidae lacks spines on the furcae; Portunidae, Calappidae, and Aethridae have two or three spines on the furcae, but differ in the size of the exopod of the antenna relative to the size of the rostrum; and Sesarmidae and Varunidae differ in the lateral spines on the carapace. A key for identification of the zoeae to the family level is presented.This is the first key for Brachyura zoeae from the southwestern Gulf of Mexico.