Eunice japonica Fauchald 1992

Eunice japonica

Eunice gracilis Moore, 1903:440–441, pl. 25: figs. 46–48.

Eunice longicirrata.—Imajima and Hartman, 1964:256 [not Eunice longicirrata Webster, 1884].

MATERIAL EXAMINED.—Holotype of E. gracilis Moore, 1903, USNM 15724, Albatross sta 3730, off Omae Zaki, Honshu Island, Japan, approximate position 34°36′N, 138°14′E, 16 May 1900, 62–67 m, mud, gravel, rock.

COMMENTS ON MATERIAL EXAMINED.—Station 3730 was a surface tow, according to the published station list; several dredge and beam trawl hauls were taken off Omae Zaki on the same day in approximately the same depths. The specimen may have come from any one of these hauls. The position indicated is that of the cape, Omae Zaki proper.

DESCRIPTION.—Holotype complete, of unknown sex, with 110 setigers; total length 50 mm; maximal width 2.5 mm; length through setiger 10, 7 mm. Body cylindrical with relatively long segments. Two pairs of anal cirri present; ventral pair long; dorsal pair very short. All anal cirri with long, cylindrical articulations.

Prostomium (Figure 59e) distinctly shorter and narrower than peristomium, less than as deep as peristomium. Prostomial lobes frontally rounded, dorsally flattened; median sulcus shallow. Eyes between bases of A-I and A-II. Antennae in horseshoe, evenly spaced, similar in thickness. Ceratophores ring-shaped in all antennae, without articulations. Ceratostyles slender, tapering; articulations long, cylindrical in A-II and A-III, nearly moniliform in A-I. Maximum 10 articulations in A-III; articulations indistinct towards bases of 3 longer antennae. A-I to middle of anterior peristomial ring; A-II to setiger 3; A-III to setiger 5. Peristomium cylindrical. Separation between rings distinct on all sides, but especially distinct dorsally; anterior ring ~ of total peristomial length. Peristomial cirri to posterior half of prostomium, slender and tapering, with 3 or 4 indistinct articulations.

Maxillary formula 1+1, 8+9, 8+0, 7+11, and 1+1; maxillae slender and teeth even in size in each maxilla.

Branchiae present, pectinate, distinctly longer than notopodial cirri, not reduced in mid-body region, erect. Branchiae from setiger 4 to 46, terminating well before posterior end, present on less than 55% of total number of setigers. First 2 and last 2 or 3 pairs single filaments. All other branchiae pectinate with up to 11 filaments. Stems slender, erect. Filaments slender.

Anterior neuropodial acicular lobes distally truncate; median acicular lobes increasingly triangular; posterior acicular lobes bluntly pointed; aciculae emerging at midline. Pre- and postsetal lobes low, transverse folds. First 3 ventral cirri thick, tapering. Inflated bases never very distinct, ovate; narrow tips large and tapering. Postbranchial ventral cirri gradually becoming tapering and finally digitiform. Notopodial cirri prominent in anterior setigers, becoming shorter in far posterior setigers. Anterior notopodial cirri basally somewhat inflated, with 2 or 3 articulations. Postbranchial notopodial cirri less distinctly basally inflated. Articulations missing from early branchial setigers.

Most setae broken. Shafts of compound falcigers (Figure 59c) inflated, marginally smooth. Appendages narrow, slightly tapering; heads indistinct, bidentate. Proximal teeth shorter than distal teeth, forming a wide-based, low triangular projection. Distal teeth tapering, narrow, nearly erect. Guards symmetrically bluntly pointed; mucros absent. Pseudocompound falcigers and compound spinigers absent. Up to 3 aciculae (Figure 59b) present, yellow, pointed, very nearly straight or very gently curved ventrally; cross-sections round. Separation between core and sheath indistinct in both aciculae and subacicular hooks. Subacicular hooks (Figure 59a, d) yellow, bidentate. Hooks first present from setiger 34, present in all setigers thereafter, paired in some setigers. Hooks tapering; heads large. Proximal teeth very much larger than distal teeth, triangular, directed slightly basally. Distal teeth triangular, erect. Secondary subacicular hooks (Figure 59d), when present, resembling primary hooks, except proximal teeth strongly parrot-beaked.

UNKNOWN MORPHOLOGICAL FEATURES.—Relationship between Mx III and left Mx IV; structure of pectinate setae.

EXPECTED STATES OF SELECTED UNKNOWN FEATURES.—None.

CHARACTERS USED IN PREPARATION OF KEY NOT SCORED.—Inappropriate Characters: 56, 58, 59. Unknown Characters: 4, 6, 42, 65–68.

ASSUMED STATES FOR PURPOSE OF PREPARING KEY.—None.