Taxonomic Descriptions of One New Species and Redescription of Four Species in the Family Strombidiidae (Ciliophora, Oligotrichida)1

Five ciliate species collected from the Woods Hole area were examined by protargol silver impregnation and scanning electron microscopy. These ciliates have been shown to sequester and use chloroplasts obtained from flagellate prey. One new species, Strombidium chlorophilum, is described. Four other species, Strombidium capitatum (Leegaard, 1915) Kahl, 1932, Strombidium conicum (Lohmann, 1908) Wulff, 1919, Strombidium acutum (Leegaard, 1915) Kahl, 1932, and Laboea strobila Lohmann, 1908, are redescribed. Characters used in describing the Strombidiidae include cell size and shape, anterior and ventral polykinetids, macronuclear shape and size, the kinetid “girdle,” the ventral kinety, the trichites, and the paroral kinety. The rationale for using these characters as taxonomic criteria is discussed.