Chave de identificação para o primeiro estágio larval (zoea I) dos camarões anfídromos (Decapoda: Caridea) do Brasil

Abstract

Amphidromy, a migratory pattern characterized by the development of planktonic larvae in estuarine waters and coastal zones while adults live and reproduce in freshwater, is observed in the life cycle of some species of caridean shrimps. In Brazil, amphidromous shrimps are represented by the families Atyidae, with the genera Atya Leach, 1816, and Potimirim Holthuis, 1954, and Palaemonidae, with the genera Macrobrachium Spence Bate, 1868, and Palaemon Weber, 1795. Accurate identification and understanding of the planktonic larvae of these shrimps are essential for ecological studies, population dynamics, taxonomy, and phylogenetics of these species. This study aimed to investigate the potential of the morphology of the first larval stage (zoea I) for identifying amphidromous shrimp species occurring in Brazil, through the development of a dichotomous identification key. A bibliographic review was conducted to select studies describing the larvae of amphidromous shrimps found in Brazil. Based on the external morphological characters of the first larval stage (zoea I), we developed a dichotomous key covering 15 taxa, of which 12 were identified at the species level. Additionally, we created illustrated plates detailing the relevant external morphological characters to facilitate the use of the dichotomous key. We conclude that the available descriptions in the literature of zoeas I of amphidromous shrimp species occurring in Brazil are effective for species identification, providing a foundation for the development of a dichotomous identification key.