Homosexual mating in the planktonic copepod Pseudodiaptomus annandalei (Copepoda: Calanoida)

Abstract

We describe homosexual pairing and spermatophore transfer from the calanoid copepod Pseudodiaptomus annandalei. The sexually dimorphic right first antenna of a male clasped another male's caudal setae followed by grasping of the urosome by the fifth swimming leg (P5). The P5 transfered the spermatophore. The observation of spermatophore transfer between males is discussed in the light of copepod reproductive biology.