First zoeal stage of Plesionika crosnieri Chan Yu, 1991, P. ortmanni Doflein, 1902, and P. semilaevis Bate, 1888, with remarks on the early larvae of Plesionika Bate, 1888 (Crustacea, Decapoda).

ABSTRACT

The morphology of first stage zoea larvae of three pandalid shrimps Plesionika crosnieri Chan Yu, 1991, P. ortmanni Doflein, 1902, and P. semilaevis Bate, 1888 are described for the first time from larvae obtained in laboratory culture. The zoea I is compared amongst those species of the genus Plesionika with larval morphology known. It is found that the length of the rostrum, the number of anteroventral denticles on the carapace, presence of exopodal setae in the maxillule, and setation pattern of the peduncle of antennule, endopod of antenna, and coxa/basis of maxillipeds are useful characters in distinguishing these larvae.