Eunice flaccida Grube 1869

Eunice flaccida Grube, 1869

Eunice flaccida Grube, 1869:491–492.

MATERIAL EXAMINED.—Holotype, ZMB 496, Tor, Red Sea, coll. Ehrenberg, Sep ?year.

COMMENTS ON MATERIAL EXAMINED.—The pectinate setae were somewhat difficult to study due to the amount of debris attached.

DESCRIPTION.—Holotype incomplete, of unknown sex, with 43 setigers; length 27 mm; maximal width 2.5 mm at setiger 10; length through setiger 10, 8.5 mm. Anterior part of body through setiger 15 cylindrical; remainder dorsoventrally flattened.

Prostomium (Figure 46a) distinctly shorter and narrower than peristomium, as deep as of the peristomium. Prostomial lobes frontally rounded, dorsally inflated; median sulcus shallow. Eyes not observed. Antennae in a horseshoe with A-I anterior to A-II and III, evenly spaced, similar in thickness. Ceratophores ring-shaped in all antennae, without articulations. Ceratostyles tapering, articulated to bases, with up to 18 short, moniliform articulations in A-III. A-I to bases of peristomial cirri; A-II to setiger 1; A-III to setiger 2. Peristomium cylindrical with strongly jutting, muscular lower lip. Separation between rings distinct only ventrally; anterior ring 5/6 of total peristomial length. Peristomial cirri to middle of anterior peristomial ring, digitiform, with 6 articulations.

Jaws not examined.

Branchiae (Figure 46b) present, pectinate, distinctly shorter than notopodial cirri, erect. Branchiae from setiger 7 to end of fragment. All branchiae pectinate; maximum 9 filaments at setiger 12; numbers of filaments decreasing posteriorly, at end of fragment 2 or 3 filaments. Branchial stems stout, cylindrical, shorter than filaments. Filaments digitiform, shorter than notopodial cirri.

Anterior neuropodial acicular lobes symmetrically truncate, becoming asymmetrically rounded with aciculae emerging above midline. Presetal lobes low, somewhat asymmetrical folds with low side ventrally. Postsetal lobe low asymmetrical folds with low side dorsally. Ventral cirri thick and rounded in all setigers, developing long digitiform tips in posterior setigers present, possibly distorted in fixation. Anterior notopodial cirri short, inflated, becoming longer posteriorly, but retaining distinct inflated basal section, without articulations.

Limbate setae slender, marginally smooth. About 5 pectinate setae in a parapodium. Pectinate setae tapering, flat. Marginal teeth about as long as other teeth, with 15 teeth. Shafts of compound falcigers (Figure 46d) gently inflated, marginally smooth; beaks indistinct. Appendages large; heads large, bidentate. Teeth similar in size. Proximal teeth narrowly triangular, directed laterally. Distal teeth tapering, directed obliquely distally. Guards asymmetrically bluntly pointed, marginally serrated; mucros absent. Pseudocompound falcigers and compound spinigers absent. Aciculae (Figure 46e) paired, yellow; exposed portion twisted in double curve, sharp tipped; distal end when worn slightly knobbed; cross-section round. Separation between core and sheath indistinct in both aciculae and subacicular hooks. Subacicular hooks (Figure 46c) yellow, tridentate with teeth in tandem. Hooks first present from setiger 27, present in all setigers thereafter, always single (except for replacements). Shafts strongly curved distally, tapering. Two lower fangs, including largest and smallest arranged on either side of middle fang, which clearly outreach other fangs.

UNKNOWN MORPHOLOGICAL FEATURES.—Jaw structure; characters associated with posterior setigers, including branchial distribution; pygidium and anal cirri.

EXPECTED STATES OF SELECTED UNKNOWN FEATURES.—Mx III long, located behind left Mx II.

CHARACTERS USED IN PREPARATION OF KEY NOT SCORED.—Inappropriate Characters: 51, 54, 55. Unknown Characters: 1, 2, 13, 14, 33, 36–38, 40, 47, 50, 57–60, 63.

ASSUMED STATES FOR PURPOSE OF PREPARING KEY.—None.