Autolytus ussuriensis Zachs, 1933

Nygren, Arne, 2004, Revision of Autolytinae (Syllidae: Polychaeta)., Zootaxa 680, pp. 1-314 : 189-190

Autolytus ussuriensis Zachs, 1933 (Fig. 97A–B)

Autolytus ussuriensis Zachs, 1933: 127 –128; Uschakov 1955: 173.

Material examined. Japanese Sea: holotype, ZIL 21056, 140 m.

Description. Holotype in very poor condition, prostomium and anterior part of dorsum dissected, and the specimen has probably been put in canada­balsam and later been transferred to alcohol (Fig. 97A). Length 10.5 mm, width 0.4 mm. Specimen yellowish, with brown dorsal cirri. Body width fairly constant with tapering end. Ciliation not possible to assess.

Prostomium and palps not possible to evaluate. Nuchal epaulettes not possible to detect as the specimen is badly damaged.

Anterior appendages in poor shape, not evaluated. Alternation in direction of cirri not assessed. Cirri in anterior 20–30 chaetigers alternate in length, in more posterior chaetigers cirri more equal; short cirri 1/3 of body width, long cirri c. 1/2 of body width; cirri in posterior region 1/3–1/2 of body width. Cirrophores possibly present on tentacular cirri, and all dorsal cirri. What is seen as cirrophores could though be an artefact. All appendages cylindrical.

Pharynx and proventricle lost.

Parapodial lobes not possible to evaluate. Aciculae not possible to examine. Chaetal fascicle with 15–20 compounds in anterior chaetigers, 5–10 in median and posterior. Compound chaetae with small distal tooth (Fig. 97B); serration present. Single thin bayonet chaetae present in posterior chaetigers. Anal cirri lost.

Reproduction. Unknown

Habitat. Unknown.

Distribution. North West Pacific. Japanese Sea. Only known from type locality.

Remarks. According to the very brief description of Zachs, this species has a trepan with 42 teeth of unequal sizes, 2–4 larger alternating with 1–3 smaller, arranged in 8 groups. The preserved specimen is described as having 2 rows of brown colour markings along the cirri, and the parapodia is light brown; 3–5 aciculae is present. As the material is in very bad shape and the pharyngeal region is dissected, these observations could not be confirmed. The species is only known from this single individual, and new material is essential for a more appropriate evaluation. The trepan structure would be unique for this taxon if it is correctly described. Due to missing information, poor description, and bad shape of type material, A. ussuriensis is considered as incertae sedis with unknown position within Autolytinae .