Portal de Periódicos da CAPES

Sperm structure of Rhopalura littoralis (Orthonectida)

2002; Wiley; Volume: 121; Issue: 2 Linguagem: Inglês

10.1111/j.1744-7410.2002.tb00049.x

1744-7410

George S. Slyusarev, Marco Ferraguti,

Coral and Marine Ecosystems Studies

Abstract. We present here a description of the spermatozoon of Rhopalura littoralis , the first fine‐structural study of an orthonectid sperm. The spermatozoon contains a slightly elongate nucleus and two centrioles orientated along the longitudinal axis of the sperm. The proximal centriole bears one rootlet. A single mitochondrion is present in the mid‐piece region. An acrosome is absent. The sperm tail is a simple flagellum with 9+2 structure. We consider the orthonectan spermatozoon to be closer in structure to those of Porifera, Cnidaria, and Annelida, than to Aschelminthes and Platyhelminthes, to which orthonectids have previously been allied.