Comprehensive Description
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İngilizce
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Smithsonian Contributions to Zoology tarafından sağlandı
Eunice reducta Fauchald, 1970
Eunice reducta Fauchald, 1970:39–43, pl. 5: figs. a–i.
MATERIAL EXAMINED.—Holotype, AHF Poly 0338, Gulf of California, Mexico, entrance of Bahia Agua Verde, from 25°31′36″N, 111°03′15″W to 25°31′40″N, 111°04′13″W, 42–48 m, dredge, sand, mollusks, crabs, 17 Mar 1949, Velero IV, sta 1743–49.
DESCRIPTION.—Holotype complete with 298 setigers; total length 318 mm; maximal width 6 mm; length through setiger 10, 15 mm. Body anteriorly truncate, cylindrical, tapering slowly posteriorly to slender posterior end with crowded short segments; most body segments only slightly wider than long; parapodia strictly lateral. Paired anal cirri barely longer than pygidium, without articulations; dorsal edge of pygidium smooth.
Prostomium (Figure 96a) distinctly shorter and narrower than peristomium, as deep as of the peristomium. Peristomial lobes frontally obliquely truncate, dorsally excavate with a thickened rim; median sulcus shallow, but wide. Eyes posterior to bases of A-I, black. Antennae in a horseshoe, evenly spaced, similar in thickness. Ceratophores ring-shaped in all antennae, without articulations. Ceratostyles digitiform, with up to 3 cylindrical, indistinct articulations. A-I to middle of anterior peristomial ring; A-II and A-III to posterior peristomial ring; A-III slightly longer than A-II. Peristomium cylindrical; lower lip distinct muscular. Separation between rings distinct dorsally and ventrally; anterior peristomial ring of total peristomial length. Peristomial cirri to middle of anterior peristomial ring, tapering, without articulations.
Maxillary formula 1+1, 4+4, 8+0, 4+10, and 1+1 according to Fauchald (1970:42).
Branchiae (Figure 96g) present, pectinate, distinctly longer than notopodial cirri, not reduced in mid-body region, erect. Branchiae from setiger 4 to setiger 131. Branchiae terminating well before posterior end, present on less than 55% of the total number of setigers. Last 6 pairs single filaments, all others with at least 2 filaments; maximum number of filaments 21 in a trim series. Branchial stems long, erect, tapering. Filaments short, digitiform. Some filaments furcate. Filaments and notopodial cirri similar in length.
Anterior neuropodial acicular lobes distally truncate with aciculae emerging at midline. Posterior neuropodial acicular lobes conical with aciculae emerging at tip. All pre- and postsetal lobes low folds. First 4 ventral cirri thick, tapering. Ventral cirri basally inflated from about setiger 5 through about setiger 50. Inflated ventral cirri large, irregularly rounded; narrow tips absent. Ventral cirri increasingly digitiform in far posterior setigers, but always shorter than notopodial cirri. Anterior notopodial cirri thick, medially inflated, decreasing rapidly in width posteriorly. Postbranchial notopodial cirri half as long as anterior notopodial cirri, slender, digitiform. Pre-branchial and branchial notopodial cirri with 2 or 3 articulations; postbranchial notopodial cirri without articulations.
Limbate setae tapering, marginally pilose. Pectinate setae (Figure 96d,f) with flattened shafts; blades flat, flaring. One marginal tooth very much longer than other teeth; ~20 teeth in median and posterior setae; ~10 in anterior setae. Shafts of compound falcigers (Figure 96b,e,h) thick, tapering, marginally smooth. Appendages short, triangular, bidentate. Proximal teeth very much smaller than distal teeth; anterior proximal teeth small, distally directed spur; posterior proximal teeth low, triangular elevations. Distal teeth very large, blunt, erect. Guards asymmetrically bluntly pointed; mucros absent. Pseudocompound falcigers and compound spinigers absent. Aciculae paired in anterior setigers, single in posterior setigers, dark brown to black, tapering, blunt-tipped; cross-section round. Subacicular hooks (Figure 96c) dark brown to black, bidentate. Hooks first present from setiger 45, present in all setigers thereafter, always single (except for replacements). Hooks tapering gently to small head. Proximal teeth about half as large as distal teeth; both teeth directed distally.
UNKNOWN MORPHOLOGICAL FEATURES.—Relationship between Mx III and left Mx IV.
EXPECTED STATES OF UNKNOWN MORPHOLOGICAL FEATURES.—Mx III forming part of a distal arc with left Mx IV.
CHARACTERS USED IN PREPARATION OF KEY NOT SCORED.—Inappropriate Characters: 56, 58, 59. Unknown Characters: 4, 6, 42, 74, 78.
ASSUMED STATES FOR PURPOSE OF PREPARING KEY.—None.
- bibliyografik atıf
- 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