Proceraea boreata ( Imajima, 1966 ) Imajima, 1966

Nygren, Arne, 2004, Revision of Autolytinae (Syllidae: Polychaeta)., Zootaxa 680, pp. 1-314 : 46-47

Proceraea boreata ( Imajima, 1966) comb. n. (Fig. 8A–D)

Autolytus (Regulatus) boreatus Imajima, 1966: 75 –77, fig. 24A–H.

Material examined. Japan: 1 paratype NSMT­Pol P­ 3, Cape Shiriyazaki, 140 m. Diagnosis. Proceraea with 2 longitudinal lines; trepan with 18 large and 9 smaller teeth, arranged in 2 rings.

Description. Length 14 mm for 64 chaetigers, complete, width 0.4 mm. Preserved material yellowish with 2 longitudinal brownish lines (Fig. 8A, B); eyes brownish red. Ciliation not possible to assess.

Eyes large, almost confluent (Fig. 8A); eye spots absent. Palps in dorsal view projecting c. 1/3 of prostomial length, fused. Extension of nuchal epaulettes to end of tentacular segment (Fig. 8A).

Antennae and anterior appendages lost or broken. Alternation in direction of cirri not assessed. Dorsal cirri from chaetiger 3, of equal length, 1/4 of body width. Cirrophores on tentacular segment and first dorsal cirri present; cirrophores otherwise absent. All appendages cylindrical, including lost anterior appendages ( Imajima 1966).

Parapodial lobes rounded conical, small. Anterior chaetigers with 2 aciculae, 1 in median and posterior. Chaetal fascicle with 10–12 compounds in anterior chaetigers, 6–10 in median and posterior. Compound chaetae with small distal tooth (Fig. 8C); serration present. Single thick bayonet chaetae, beginning at chaetiger 30.

Pharynx with sinuation anterior to proventricle. Trepan with 27 unequal teeth; 18 large and 9 smaller; 2 large alternating with 1 small, arranged in 2 rings. Basal ring present; infradental spines absent. Proventricle equal in length to 2 segments in chaetiger 6–7 with c. 37 rows of muscle cells (Fig. 8D). Anal cirri equal in length to dorsal cirri.

Reproduction. Anterior scissiparity (Fig. 8B).

Habitat. Unknown.

Distribution. North East Pacific. Northern Japan.

Remarks. Proceraea boreata is very similar to P. okadai Imajima, 1966 ; in external features they are inseparable, and differ only in the number of teeth in the trepan.