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Eunice rubrivittata (Treadwell 1921)

Comprehensive Description

provided by Smithsonian Contributions to Zoology
Eunice rubrivittata (Treadwell, 1921)

Leodice rubrivittata Treadwell, 1921:34–36, figs. 85–94, pl. 1: fig. 18.

Eunice vittata.—Augener, 1927:40.—Hartman, 1956:252 [in part, not Nereis vittata Chiaje, 1829].

MATERIAL EXAMINED.—Holotype, AMNH 1263, Buccoo Bay, Tobago land, 8 Apr 1918.

DESCRIPTION.—Holotype incomplete with 97 setigers; length 56 mm; maximal width 1.2 mm; length through setiger 10, 5.1 mm.

Prostomium and peristomium about equal in length (Figure 99a), distinctly narrower than peristomium, less than as deep as peristomium. Prostomial lobes frontally rounded, dorsally slightly flattened; median sulcus deep. Eyes not observed. Antennae in a horseshoe, evenly spaced, similar in thickness. Ceratophores ring-shaped in all antennae, without articulations. Ceratostyles distally blunt, digitiform, with 2 or 3 irregularly arranged, cylindrical articulations. A-I to middle of peristomium; A-II and A-III to setiger 1. Peristomium cylindrical. Separation between rings distinct on all sides of body; anterior ring slightly longer than posterior ring. Anterior ring with frontal, yoke-shaped thickening covering at peristomial fold. Peristomial cirri incomplete, probably slender and digitiform.

Jaws not available.

Branchiae (Figure 99e) present, pectinate, distinctly shorter than notopodial cirri, not reduced in mid-body region, flexible. Branchiae from setiger 3 to setiger 56. Branchiae terminating well before posterior end, present on less than 55% of total number of setigers. First 6 branchiae single, long filaments which increase somewhat in length posteriorly. From setiger 9 another filament added; maximum 5 filaments from setiger 25 to 40. Number of filaments reduced to 1 by setiger 45.

Anterior neuropodial acicular lobes distally obliquely transverse with distinct, rounded lobes dorsal to emergence of aciculae; posterior acicular lobes increasingly withdrawn into body wall with aciculae emerging from tips; subacicular hooks supporting a secondary, flattened conical structure along ventral edge of parapodium (Figure 99b). All pre- and postsetal lobes follow outline of acicular lobes closely. First 5 or 6 ventral cirri digitiform. Ventral cirri basally inflated from setiger 6 through setiger 50. Inflated bases nearly spherical; narrow tips digitiform. Ventral cirri digitiform from setiger 60, emerging well distal to bases of parapodia. Anterior notopodial cirri tapering, with 2 or 3 indistinct cylindrical articulations. Posterior notopodial cirri long, digitiform, without articulations.

Limbate and pectinate setae not observed. Shafts of compound falcigers (Figure 99c) inflated, marginally smooth. Appendages bidentate. Proximal teeth much larger than distal teeth. Distal teeth directed obliquely distally. Guards with very short distal mucros. Pseudocompound falcigers and compound spinigers absent. Aciculae single, yellow, tapering, straight; cross-sections round. Notopodial aciculae distinct in anterior and median setigers. Separation between core and sheath indistinct in both aciculae and subacicular hooks. Subacicular hooks (Figure 99d) yellow, tridentate with teeth in a crest. Hooks first present from setiger 31, present in all setigers thereafter, always single (except for replacements). Hooks with very large, curved main fangs; fangs decreasing in size to very short tertiary fang.

UNKNOWN MORPHOLOGICAL FEATURES.—Jaw structure; pectinate setae; pygidium and anal cirri.

EXPECTED STATES OF UNKNOWN MORPHOLOGICAL FEATURES.—None.

CHARACTERS USED IN PREPARATION OF KEY NOT SCORED.—Inappropriate Characters: 56, 58, 59. Unknown Characters: 1, 2, 4, 6, 13, 14, 27–29, 65–68.

ASSUMED STATES FOR PURPOSE OF PREPARING KEY.—None.
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bibliographic citation
Fauchald, Kristian. 1992. "A Review of the Genus Eunice (Polychaeta: Eunicidae) Based upon Type Material." Smithsonian Contributions to Zoology. 1-422. https://doi.org/10.5479/si.00810282.523