Presence of two suctorian ciliate species of the genera Acineta and Pelagacineta, epibionts on marine copepod crustaceans.

Acineta arcachoniensis sp. nov., a new species of protist suctorian epibiont on the copepod Chiridius gracilis is described. The individuals show two well-developed actinophores, with two fascicles of capitate tentacles, an irregular nucleus, a cup-shaped lorica and a short stalk. Reproduction of A. arcachoniensis is by endogenous budding. The suctorians are located on the base of the antennae, the final abdominal segments or on the last pereiopod pair of the copepod. In addition, a new registration of the suctorian Pelagacineta euchaetae on the copepod Calanus helgolandicus is recorded.