The first snapshot study on horizontal distribution and identification of five peritrich ciliates (Genus Vorticella Linnaeus and Zoothamnium Bory de St. Vincent) from the eastern Indian Ocean

摘要

Epipont peritrich ciliates are one of the most sessilie protists that attached to the substrate of zooplankton communities especially copepods and crustaceans.Peritrich ciliates can be solitary or colonial form found from the coastal zones and embayment around the world.Present research report is the first snapshot study of the peritrich ciliates and the horizontal distribution in open waters from surface to 200 m depth in the eastern Indian Ocean.Recently,five peritrich ciliates,e.g.,Vorticella oceanica,Zoothamnium alternans,Z.alrasheidi,Z.pelagicum,and Z.marinum were collected from plankton net tow samples during the cruise from April 10 to May13,2014.The characteristics of the peritrich ciliate were determined according to the shape of the zooids,the ciliary structure and the stalks.The morphometric shape,sizes and characters also explained by examination under light/scanning electron microscopy.Vorticella oceanica and Z.pelagicum showed their association with host such as diatom(i.e,Chaetoceros coarctatus)and copepod(Oithona brevicornis)including some individuals around the dinoflagellate species(Ceraitum tripose).The distribution of these sessilid ciliates was dominated by the V.oceanica,Z.pelagicum and Z.marinum at the southeast zone while the large colonies of Z.alrasheidi observed at the Bay of Bengal.This distribution can be influenced by substrate availability like diatom(Ch.coarctatus)and copepods(O.brevicornis).