Abstract
This study aims to investigate the embryonic development of Esanthelphusa nani, a common rice field crab found in paddy fields of northern Thailand, using confocal laser scanning microscopy. We found that the development of E. nani can be achieved in eggs within 12 days resulting in a hatchling stage corresponding to megalopa stage. Pre-organogenetic stages were characterized by a superficial cleavage including egg-cleavage, egg-blastula and egg-gastrula. Organogenesis stages were identified by appendage appearances and can be divided into egg-nauplius, egg-zoea and egg-megalopa. After hatching, crabs metamorphose to juveniles. By providing new comparative data, our study shed some new light on the relationship between environment, phylogeny and development; and opens potential area of research in an eco-evo-devo perspective.