Eunice sonorae Fauchald 1970

Eunice sonorae Fauchald, 1970

Eunice sonorae Fauchald, 1970:45–48, pl. 6: figs. a-g.

MATERIAL EXAMINED.—Holotype, AHF Poly 0283, Puerto Penasco, Sonora, Mexico, rocky intertidal, 8 Apr 1967, coll. P. Pickens.

DESCRIPTION.—Holotype complete with 586 setigers; total length 345 mm; maximal width 6 mm; length through setiger 10, 14 mm. Anterior body cylindrical, tapering slowly, with numerous, very crowded segments posteriorly. Anal cirri long, tapering, without articulations.

Prostomium (Figure 104e) distinctly shorter and narrower than peristomium, as deep as of peristomium. Prostomial lobes frontally obliquely truncate, dorsally flattened; median sulcus deep. Eyes behind bases of A-I, black. Antennae in a horseshoe, evenly spaced, similar in thickness. Ceratophores long, confluent with prostomium, without articulations. Ceratostyles slightly tapering, with a maximum of 4 irregular, cylindrical articulations in A-III. A-I to anterior peristomial ring; A-II to posterior edge of peristomium; A-III to setiger 1. Peristomium with very voluminous, muscular lower lip, otherwise cylindrical. Separation between rings distinct on all sides; anterior ring of total peristomial length. Peristomial cirri to middle of anterior peristomial ring, without articulations.

Jaws not examined.

Branchiae (Figure 104h) present, pectinate, distinctly longer than notopodial cirri, not reduced in mid-body region, flexible. Branchiae from setiger 41 to setiger 530. Branchiae terminating well before posterior end, present on more than 65% of total number of setigers. First branchia with 2 filaments; maximum 6 filaments from about setiger 65; from about setiger 400 number of filaments decreasing and length of filaments decreasing rapidly. From setiger 475 branchiae very short, tapering single filaments decreasing in size posteriorly. Branchial stem very slender. Filaments very long, slender, nearly filiform.

Anterior neuropodial acicular lobes (Figure 104f) obliquely truncate with aciculae emerging near midline. Posterior acicular lobes symmetrically rounded with aciculae emerging slightly superior to middle. All presetal lobes low, transverse folds. Anterior postsetal lobes twice as high as acicular lobes, symmetrically rounded. Postsetal lobes decreasing in size posteriorly, retained as short rounded free lobes superior to and behind acicular lobe in all setigers. First 4 ventral cirri thick and tapering. Ventral cirri basally inflated from about setiger 5 through rest of body. Inflated bases thick, elongated welts, less conspicuous posterior to setiger 450; narrow tips tapering. Anterior notopodial cirri medially inflated; posterior notopodial cirri tapering from a wide base, retaining about same length in all setigers. Notopodial cirri without articulations.

Anterior setigers with thick supra-acicular and posterior fascicles of limbate setae and masses of compound falcigers in subacicular and anterior positions; pectinate setae absent. Median and posterior setigers with thinner fascicles of limbate setae and compound falcigers; pectinate setae present. Limbate setae slender, marginally smooth. Posterior pectinate setae in large numbers; some pectinate setae (Figure 104i) unusually large; shafts flattened; blade flat, widely flaring. One marginal tooth longer than other teeth; ∼16 teeth present Shafts of anterior compound falcigers (Figure 104g) tapering, with distinct internal striations, marginally smooth, without distal beak. Appendages slender, slightly tapering, bidentate. Proximal teeth much smaller than distal teeth, tapering, directed distally. Distal teeth nearly erect, thick, blunt. Shafts of posterior compound falcigers (Figure 104j) inflated, without internal striation, marginally finely serrated; distal beak present. Appendages shorter than in anterior setigers; heads distinct, rather large, bidentate. Proximal teeth larger than distal teeth, triangular, laterally directed. Distal teeth tapering, directed laterally. Guards symmetrically rounded in all setigers, smooth-edged in anterior setigers, marginally serrated in posterior setigers; mucros absent, Pseudocompound falcigers and compound spinigers absent. Notopodial aciculae honey-colored and especially prominent in posterior setigers. Aciculae up to 4 in anterior setigers, becoming reduced to 1 in posterior setigers, with dark brown to black cores and clear sheaths, tapering to slender, straight tips; cross-sections round. Subacicular hooks (Figure 104k) with dark brown to black cores and clear sheaths, tapering to slender single tips. Hooks first present from setiger 54, present in all setigers thereafter, always single (except for replacements). Hooks slender, distally abruptly tapering to simple, blunt tips.

UNKNOWN MORPHOLOGICAL FEATURES.—Jaw structure.

EXPECTED STATES OF UNKNOWN MORPHOLOGICAL FEATURES.—Mx III short; forming part of distal are with left Mx IV.

CHARACTERS USED IN PREPARATION OF KEY NOT SCORED.—Inappropriate Characters: 56, 60. Unknown Characters: 4, 6.

ASSUMED STATES FOR PURPOSE OF PREPARING KEY.—None.