Eunice articulata Ehlers 1887

Eunice articulata Ehlers, 1887

Eunice articulata Ehlers, 1887:83, pl. 24: figs. 8–10.

MATERIAL EXAMINED.—TWO syntypes, MCZ 140 and 799, Blake, 3 Apr 1869, off French Reef, Cast No. 1, 15 fathoms.

COMMENTS ON MATERIAL EXAMINED.—The two syntypes do not belong to the same taxon; the specimen from MCZ 140 belongs to group B, probably to subgroup 2, the one from MCZ 799 to group A-1. The species has been considered related to E. websteri (= E. longicirrata Webster) and Ehlers description matches the specimen from MCZ 799; thus the following description is based on this specimen. The specimen from MCZ 140 is briefly characterized at the end of this description. The syntype from MCZ 799 previously has been dry.

DESCRIPTION.—Syntype incomplete, of unknown sex, with 132 setigers; length about 50 mm; width more than 3 mm; length through setiger 10 not determined. Body cylindrical, dorsoventrally flattened medially.

Prostomium (Figure 16a) distinctly shorter than and narrower than peristomium, less than as deep as peristomium, bent dorsally. Prostomial lobes frontally truncate, dorsally inflated; median sulcus deep. Eyes lateral to bases of A-I. Antennae in transverse row, evenly spaced; A-III distinctly heavier than other antennae. Ceratophores ring-shaped in all antennae, without articulations. Ceratostyles slender and tapering; articulations cylindrical, becoming increasingly drop-shaped distally; maximum 17 articulations in A-III. A-I to setiger 5; A-II to setiger 7; A-III to setiger 11. Peristomium cylindrical. Separation between rings distinct only dorsally; anterior ring of total peristomial length. Peristomial cirri reaching well beyond prostomium, about as long as A-I, extremely slender, nearly filiform, with 6 very long articulations.

Maxillary formula 1+1, 5+6, 5+0, 4+7, and 1+1.

Branchiae (Figure 16e) present, pectinate, distinctly longer than notopodial cirri, not reduced in mid-body region, erect. Branchiae from setiger 4 through setiger 55. Branchiae terminating well before posterior end, present on less than 55% of total number of setigers. First and last 2 or 3 pairs single filaments; maximum 6 filaments at about setiger 15. Branchiae and filaments shorter than notopodial cirri in anterior branchial region; both longer than notopodial cirri in posterior branchial setigers. Stems thick, tapering, longer than filaments. Filaments digitiform, slender in anterior setigers.

Shape of neuropodia indeterminable. Median ventral cirri basally inflated; postbranchial ventral cirri slender, digitiform. Anterior notopodial cirri long, slender, nearly filiform, with 3 cylindrical articulations, much longer than branchiae. Median and postbranchial notopodial cirri short, tapering, without articulations.

Limbate setae straight, narrowly limbate. Pectinate setae numerous. Shafts of pectinate setae (Figure 16d) cylindrical, slender. Blades tapering, flat. One marginal tooth longer than other teeth; 15 teeth present. Shafts of compound falcigers (Figure 16c) tapering, marginally smooth, without internal striations or distal beak. Appendages large, with parallel sides; basal boss distinct; head large, bidentate. Proximal teeth triangular, directed laterally. Distal teeth larger than proximal teeth, thick, directed obliquely distally. Guards symmetrically bluntly pointed, marginally serrated, without mucros. Pseudocompound falciger and compound spinigers absent. Aciculae yellow, 2–3 in a parapodium, distally pointed, straight; cross-section round. Separation of core and sheath indistinct in both aciculae and subacicular hooks. Subacicular hooks (Figure 16b) yellow, bidentate. Hooks first present from setiger 40, present in all setigers thereafter, always single (except for replacements). Hooks tapering smoothly to tips; heads small. Proximal teeth larger than distal teeth, directed laterally. Distal teeth tapering, directed obliquely distally.

Syntype from MCZ 140 frontally deeply dissected, with 80 setigers; length 55 mm. Maxillary formula 1+1,4+4, 6+0, 4+7, and 1+1. Branchiae from setiger 5 to end; all branchiae pectinate with erect stems. Shafts of pectinate setae slender, cylindrical; blades distinctly flaring, flat. One marginal tooth longer and thicker than the other teeth; ~25 teeth. Aciculae paired, black, distally bent. Subacicular hooks from setiger 32, black, bidentate.

UKNOWN MORPHOLOGICAL FEATURES.—Characters associated with posterior end; relationship between Mx III and left Mx IV; neuropodial structures.

EXPECTED STATE OF SELECTED UNKNOWN FEATURES.—MX III long, straight, located behind left Mx II; distal arc absent; Mx VI absent.

CHARACTERS USED IN PREPARATION OF KEY NOT SCORED.—Inappropriate Characters: 56, 58, 59. Unknown Characters: 1,2, 4–6, 43–49, 51, 52, 54, 55.

ASSUMED STATES FOR PURPOSE OF PREPARING KEY.—None.

Eunice articulata (Hoagland, 1920)

Leodice articulata Hoagland, 1920:615–616, pl. 50: figs. 9–12.

?Eunice articulata.—Hartman, 1959:316.