Pelagacineta Jankowski 1978

Pelagacineta sp.

(Fig. 2F)

Material Examined: One individual as epibiont on pelagic ostracod Cypridina dentata (Müller, 1906) from station 16.

Brief Description: Suctorian ciliate with thecostyle. The body is ovoid, dorso-ventrally compressed and discoidal in shape lying at the top of a thecostyle that widens considerably to form a cupped lorica-like anterior region. Numerous capitate tentacles located anteriorly and evenly distributed at cell body surface. The shape of macronucleus and mode of reproduction were not observed.

Measurements (μm) (measurement taken from one individual): body height 64; body width 109; height of anterior region of the thecostyle 57, width 34; length of stalk-like part of the thecostyle 140; diameter 19, length of the tentacles 34–67.

Remarks: Based on shape of body and dimensions, the present species is related to Pelagacineta campanula (Schröder, 1907) epibiont on marine copepods Euchaeta sp. and Metridia sp. from Antarctic waters (Schröder 1907, Curds 1987) and Pelagacineta hebensis Gregori et al. 2015 epibiont on Paraeuchaeta hebes (Giesbrecht, 1888) from continental shelf at Ria de Vigo, N. E. Atlantic waters, Galician coast, Spain (Gregori et al. 2015). Pelagacineta campanula is characterised by ribbon-like, branched macronucleus, whereas Pelagacineta hebensis has ovoid macronucleus. Since, we were not able to observe the morphology of macronucleus in present specimen, the identification of the present specimen up to species level is kept in abeyance. Present report is the first record of the genus Pelagacineta as epibiont on ostracod host and this genus is also reported for the first time from the Indian Ocean.