Balantidium sigani sp. nov., a trichostome ciliate from Red Sea rabbitfish (pisces, siganidae)

Light and scanning electron microscopic study of Balantidium ctenopharyngodoni Chen, 1955 (Class: Litostomatea) from China

Redescription of Balantidium ctenopharyngodoni "Chen (Acta Hydrobiol Sin 1:123-164, 1955)", collected from the hindgut of grass carp (Ctenopharyngodon idella), especially the segment of 6-10 cm upstream from the anus, from Honghu Lake, Hubei Province, central China in November 2005, is presented in this paper to complete Chen's description at both light and scanning electron microscopic levels. Some revisions were done: the vestibulum is fairly symmetrical, with compactly arranged cilia rather than assembled membrane bordering on the left vestibular side; four contractile vacuoles actually exist in the latter body, three of which surround the posterior portion of the macronucleus, whereas the fourth lies antero-left to it. Somatic monokinetids were compared among the species of genus Balantidium. The cysts were described, and possible infection routes of B. ctenopharyngodoni were also discussed.

Food vacuole contents in the ciliate, Balantidium jocularum (Balantididae), a symbiont in the intestine of the surgeonfish, Naso tonganus (Acanthuridae)

During the past 16 years, the ciliate Balantidium jocularum has been collected from the intestines of many specimens of its fish host, Naso tonganus, all collected from the Great Barrier Reef near Lizard Island, Australia. Ciliates for this study of food consumption were isolated in 1988, 1989, 2003, and 2005. Nineteen specimens of B. jocularum were examined in the transmission electron microscope to determine the contents of both food vacuoles and a putative discharging cytoproct vacuole. Food vacuoles contained rod-shaped bacteria, tightly coiled spirilliform bacteria, and one or more euglenid flagellates. In several balantidia of somewhat different form than the type species of B. jocularum, the large bacterium, Epulopiscium fishelsoni, was observed in light microscope protargol preparations. Some putative phagolysosomes retained spirilliform bacteria that were apparently intact, and others contained partially digested flagellates. Food in a single discharging cytoproct vacuole consisted of normal appearing spirilliform bacteria, some other bacteria, and no flagellates. The results argue for non-selective ingestion of food and selective digestion; hence, somewhat inefficient food processing.

New species of Balantidium and Paracichlidotherus (Ciliophora) inhabiting the intestines of four surgeonfish species from the Tuvalu Islands, Pacific Ocean

Four species of adult herbivorous surgeonfishes (Family Acanthuridae) were collected from the remote South-Pacific island system of Tuvalu. Their intestinal contents were examined, and of four populations of ciliated protists, two new species were discovered and are described. Ciliates were examined after protargol staining and, in some cases, scanning electron microscopy. Members of each population were examined and 10 characters measured for the balantidia, and 13 for the paracichlidotherids. A new Balantidium is described which has an unusually large dextr-oral field of cilia. A new species of Paracichlidotherus was discovered which has a macronucleus significantly smaller and well anteriad the cytoplasmic portion of the oral polykinetids relative to the type species.