Tintinnophagus acutus n. g., n. sp. (Phylum Dinoflagellata), an ectoparasite of the ciliate Tintinnopsis cylindrica Daday 1887, and its relationship to Duboscquodinium collini Grassé 1952.

摘要: The dinoflagellate Tintinnophagus acutus n. g., sp., an ectoparasite of the ciliate Tintinnopsis cylindrica Daday, superficially resembles Duboscquodinium collini Grasse, a parasite Eutintinnus fraknoii Daday. Dinospores T. are small transparent cells having sharply pointed episome, conspicuous eyespot, posteriorly positioned nucleus with condensed chromosomes, and rigid form that may be supported by delicate thecal plates. attach to host via feeding tube, losing their flagella, sulcus, girdle become spherical or ovoid cells. trophont feeds on for several days, increasing dramatically in size before undergoing sporogenesis. Successive generations daughter sporocytes encompassed outer membrane cyst wall, feature not evident trophonts. differs from D. species, absence second surrounding pre-sporogenic stages, failure differentiate into gonocyte trophocyte at first sporogenic division. Phylogenetic analyses based subunit (SSU) ribosomal DNA (rDNA) sequences placed class Dinophyceae, aligned loosely Pfiesteria piscicida related including Amyloodinium ocellatum, fish, Paulsenella vonstoschii, diatoms. Dubosquodinium nested clade composed Scrippsiella species Peridinium polonicum. Tree construction using longer rDNA (i.e. SSU through partial large subunit) strengthened placement within Dinophyceae.