Family Ophionereididae Ljungman, 1867

Synonym

Ophiochitonidae Matsumoto, 1915: 88 (see Smith, Paterson & Lafay 1995).

Type genus

Ophionereis Lütken, 1859 (type species: O. reticulata (Say, 1825)) .

Other genera

Ophiochiton Lyman, 1878a, Ophiodoris Koehler, 1904, Ophioneroides Cherbonnier & Guille, 1978, Ophioplax Lyman, 1875 .

Diagnosis

Granules along the genital slit, extending onto disc edge. Accessory dorsal arm plates ( Ophionereis). Scale-like, flat, oval to round tentacle scales. Tooth sockets dorsally as large fenestrations with septum. Arm spine articulation horse-shoe shaped, with parallel dorsal and ventral lobes proximally separated by vertical row of knobs or merged by ribbed border, framing nerve and muscle openings of almost equal size. Internal of lateral arm plate with large pore close to the dorsal edge of the tentacle pore excavation, at the ventral tip of a large ridge along the inner proximal edge that bends ventro-distalwards. Vertebrae with distally protruding dorsal keel and proximal dorsal groove.

Remarks

Most characters apply only to Ophionereis and are modified or reduced in the other genera. The unifying characters are the lateral arm plate characteristics and the arm spine articulation.