| Contents | Classes | Subclasses | Orders | Suborders | Families |
Family PENICULISTOMATIDAE Fenchel, 1965
Body kidney-shaped, large, strongly flattened laterally, densely ciliated; oral area subequatorial on ventral margin, with buccal ciliature clearly detectable; huge macronucleus; commensal in mantle caviry of marine bivalve mollusc (Mytilus edulis) but also in fresh-water clams and certain sea urchins.
| Echinosociella Berger [unpublished] . Single species. |
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| Mytilophilus Antipa & Small [unpublished] . Single species. |
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| Peniculistoma Jankowski, 1964 (syns. Conchophthirus p.p., Ciliomorgania, Demorgania, Kidderia [hom.] , Morgania [hom.] ). Single species [originally described by Kidder (1933a) as a conchophthirid; transferred to new genus by Jankowski (1964b, p. 272)] . |
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