| Leiotrocha Fabre-Domergue, 1888. Few species. |
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Family LEIOTROCHIDAE Johnston, 1938
Body cylindrical or barrel-shaped, with slightly bulging apical end; adoral spiral of ca. 400°, with radius like that of aboral adhesive disc; denticles smoothly linked, ca. 20 in number; macronucleus bulbous with two arms (roughly H-shaped); cortical rings present; widespread symbiont on gills of marine molluscs and on scattered other invertebrates (e.g., on spines of sea urchins).
[Some workers consider the genus Leiotrocha confamilial with Urceolaria, thus in the preceding family.]
| Leiotrocha Fabre-Domergue, 1888. Few species. |
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