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Image de Leodice valens Chamberlin 1919
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Leodice valens Chamberlin 1919

Comprehensive Description ( anglais )

fourni par Smithsonian Contributions to Zoology
Eunice valens (Chamberlin, 1919)

Leodice valens Chamberlin, 1919c:257–258, pl. 1: figs. 6–8.

Eunice valens.—Fauchald, 1969:10–12. fig. 5a-d.

MATERIAL EXAMINED.—Holotype, MCZ 120, Mendocino, California, coll. A. Agassiz.

DESCRIPTION.—Holotype complete with 179 setigers; total length 140 mm; maximal width 9 mm at setiger 15; length through setiger 10, 12.5 mm; width at setiger 10, 8.5 mm. Anterior part of body circular in cross-section, becoming ventrally flattened with convex dorsal side posteriorly. Anterior end truncate; body tapering slowly posteriorly to narrow pygidium. Anal cirri as long as the last 5 to 6 setigers, with 5 or 6 cylindrical articulations.

Prostomium (Figure 113k) distinctly shorter and narrower than peristomium, less than as deep as peristomium. Prostomial lobes frontally obliquely truncate, dorsally flattened; median groove shallow. Transverse grooves separating palpal region present. Dark purple eyes lateral to bases of A-II. Antennae in a horseshoe, with A-I and A-II emerging close together, separated from A-III by distinct gaps, similar in thickness. Ceratophores ring-shaped in all antennae, without articulations. Ceratostyles tapering, with up to 11 cylindrical articulations in A-III. A-I to front of posterior peristomial ring; A-II to back of posterior peristomial ring; A-III to setiger 1. Peristomium cylindrical. Separation between rings distinct dorsally and ventrally and indistinct only for short distance laterally; anterior ring of total peristomial length. Peristomial cirri to middle of anterior ring, slender and tapering, with three indistinct rings.

Maxillary formula 1+1, 6+8, 9+0, 6+8 according to Chamberlin (1919c), presumably also 1+1. Mx III long and located behind left Mx II.

Branchiae (Figure 1131) present, pectinate, distinctly longer than notopodial cirri, not reduced in mid-body region, erect. Branchiae from setiger 3 to setiger 76. Branchiae terminating well before posterior end, present on less than 55% of total number of setigers. First 2 and last 10 pairs single filaments; all other branchiae with at least 2 filaments; maximum 11 filaments. Branchial stems tapering and erect. Filaments digitiform, relatively thick; filaments about as long as notopodial cirri.

Anterior neuropodial acicular lobes symmetrically rounded with aciculae emerging dorsal to midline. Posterior acicular lobes nearly conical. All presetal lobes low folds. Anterior postsetal lobes free, triangular lobes about as high as acicular lobes, becoming low folds following outline of acicular lobes closely from about setiger 20. First 9 ventral cirri thick and tapering. Ventral cirri basally inflated from about setiger 10 through about setiger 60. Inflated bases thick transverse welts; narrow tips tapering. Posterior ventral cirri thick, tapering and reflexed behind acicular lobes in far posterior setigers. Anterior notopodial cirri basally inflated, with 3 to 4 indistinct articulations. Articulations lost in middle branchial setigers; postbranchial notopodial cirri slender, tapering, without articulations.

All limbate setae outreaching compound hooks, slender and marginally finely serrated. All pectinate setae (Figure 113n) with cylindrical, slender shafts, distally tapering, flat. One marginal tooth longer than other teeth; ~10 teeth present. Shafts of all compound falcigers (Figure 113m) very coarse, nearly as thick as aciculae, tapering from wide proximal part of hinge. Beaks absent; shafts with distinct, dark-colored cores and dark-yellowish sheaths. Appendages short, narrow and tapering to small head, bidentate. Proximal teeth short, triangular and directed laterally, more prominent in posterior than in anterior setigers. Distal teeth nearly erect in all setigers, sharply pointed in anterior setigers, tapering and blunt in posterior setigers. All guards asymmetrical, sharply pointed, but not mucronate in anterior setigers, bluntly pointed in posterior setigers. Pseudocompound falcigers and compound spinigers absent. All aciculae and subacicular hooks with core and sheath structure. Aciculae (Figure 113q) paired in most setigers, but up to 4 aciculae in some setigers, yellow, tapering to blunt tips and gently curved; cross-section round. Subacicular hooks (Figure 113p) yellow, bidentate. Hooks first present from setiger 43, present in all setigers thereafter, single in most, paired in some setigers. Hooks about as thick as aciculae, tapering to distinct, bent necks and distinct heads. Both teeth directed distally; proximal teeth larger than distal teeth.

UNKNOWN MORPHOLOGICAL FEATURES.—None.

EXPECTED STATES OF UNKNOWN MORPHOLOGICAL FEATURES.—None.

CHARACTERS USED IN PREPARATION OF KEY NOT SCORED.—Inappropriate Characters: 56, 58, 59. Unknown Characters: 42.

ASSUMED STATES FOR PURPOSE OF PREPARING KEY.—None.
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citation bibliographique
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

Comprehensive Description ( anglais )

fourni par Smithsonian Contributions to Zoology
Eunice valens (Chamberlin, 1919b)

Leodice valens Chamberlin, 1919b, pp. 257–258, pl. 1: figs. 6–8.

Eunice kobiensis.—Åkeston, 1967, pp. 141–192, figs. 1–22 [not E. kobiensis McIntosh, 1885].

? Eunice tridentata.—Hartman, 1944, pp. 114–115, pl. 7: figs. 145–150, partim [not E. tridentata Ehlers, 1905].

MATERIAL.—Mendocino, California, collection of A. Agassiz, holotype (MCZ 120) and paratype (MCZ 121).

DESCRIPTION.—The holotype is a complete specimen with 179 setigers; it is 140 mm long and 7 mm wide with setae. It is evenly pink with a slight brown tinge and lacks color pattern. The anterior end of the body is cylindrical; the median and posterior end is slightly flattened dorsally. The anal cirri are as long as the ten last setigers. The paratype has been dried out and consists of several unidentifiable fragments.

The prostomium (Figure 5b) is wider than long and has a deep anterior incision; each half is evenly rounded. A pair of black eyes is present posterior to the bases of the outer lateral occipital tentacles. Each of the outer lateral occipital tentacles has five articulations; the inner lateral ones have ten articulations each and the median tentacle has eleven articulations.

All articles are cylindrical and only faintly marked externally. The outer lateral pair of tentacles reaches the second peristomial segment and are somewhat stouter than the other tentacles. The inner lateral pair reaches the first setiger and the median tentacle reaches the second setiger.

The cylindrical first peristomial segment is twice as long as the first setiger; it projects forward like a collar and covers the bases of the occipital tentacles. The second peristomial segment is only half as long as the first setiger. The peristomial cirri are slender; each has seven or eight articulations and reaches the front edge of the first peristomial segment.

The first setigers have short, transverse presetal lobes; the setal and postsetal lobes are truncate; the setal lobes are a little longer than the presetal ones, but shorter than the postsetal lobes. The parapodia in the branchial region (Figure 5a) are similar to the first ones, but the postsetal lobes are reduced to transverse folds in the first branchial segments. The setal lobes become conical and the presetal and postsetal lobes are visible only as low folds in the postbranchial region.

The dorsal cirri are large in the prebranchial region and in the first branchial setigers; they are surpassed by the branchiae where these are fully developed even if the cirri themselves are not reduced in size. Dorsal cirri in the postbranchial region are again very prominent. Each digitiform, thickset cirrus is divided into two to five irregular articles. The thickset ventral cirri in the prebranchial and early branchial setigers are blunt; farther back the bases become very swollen, but the distinct, blunt tips of the cirri are present in all setigers.

Branchiae (Figure 5a) are present in setigers 3–76. The first two and the last eight or nine pairs are simple filaments; all others are pectinate with long, stout branchial filaments. The branchiae are best developed in setigers 15–30; the maximal number of branchial filaments is eleven.

Composite hooded hooks (Figure 5d) are found in ventral fascicles in all setigers. They have smooth shafts which are distally enlarged; each appendage is triangular with a slightly curved distal tooth; the proximal tooth is blunt and nearly at right angles with the distal one. The short hoods are blunt and serrated near the bases of the appendages. Smooth, slightly curved capillary setae are found in dorsal fascicles in all parapodia; pectinate setae were not seen. Acicula number three or four in a parapodium; each is light yellow and has a strongly bent, conical tip. Subacicular hooks (Figure 5c) are present from setiger 43 to the end of the body. Each is tapering evenly and is light yellow; the proximal tooth is larger than the distal one and only at a slight angle with the axis of the hook.

The description of the pharyngeal apparatus is rewritten from Chamberlin (1919b); it was not dissected in the holotype and the condition of the paratype does not permit confirmation of the description. The mandibles have calcified cutting edges with three rounded teeth each. Maxilla II has six teeth left and eight right; left maxilla III has eight or nine teeth; the combined right maxillae III + IV have eight teeth; left maxilla IV has six teeth. Chamberlin gave no information on the dentition of either maxillae V; his illustration of maxillae I (pl. 1: fig. 8) shows that these are strongly falcate.
licence
cc-by-nc-sa-3.0
citation bibliographique
Fauchald, Kristian. 1969. "A revision of six species of the flavus-bidentatus group of Eunice (Eunicidae: Polychaeta)." Smithsonian Contributions to Zoology. 1-15. https://doi.org/10.5479/si.00810282.6