Panthalis fauveli Pettibone 1989

Panthalis fauveli

Panthalis oerstedi.—Fauvel, 1932:39, fig. 7a–c. [Not Panthalis oerstedi Kinberg, 1856.]

MATERIAL EXAMINED.—ARABIAN SEA. Investigator sta 362, 897 m, holotype (MNHNP, as Panthalis oerstedi by Fauvel). BAY OF BENGAL, 749 m, Investigator, paratype (BMNH 1938.5.7.6, as Panthalis oerstedi by Fauvel).

TYPE MATERIAL.—Holotype with 61+ segments, 33+ mm long, 8 mm wide with setae. Paratype with 80 segments, last few small, 45 mm long, 9 mm wide, a female with large yolky eggs.

DESCRIPTION.—Elytra delicate, smooth, elongate-oval, with eccentric attachment near lateral side, with deep lateral pocket from 5th elytra (Figure 35B).

Bilobed prostomium with large ovate colorless ommatophores on anterior half of prostomium; median antenna with small ceratophore in middle of prostomium, papillate along lateral sides, with short style extending to tip of ommatophores (variable in length, according to Fauvel, 1932:39); lateral antennae arising ventral to ommatophores with tips extending beyond ommatophores; ventral palps missing on types (long, tapered, smooth, according to Fauvel, 1932:39). Tentacular segment distinct dorsally, with middorsal anterior extension; tentaculophores lateral to and fused basally to prostomium, each with single aciculum, 2 bundles of few capillary setae, long row of papillae on inner side, dorsal and ventral tentacular cirri similar to but longer than lateral antennae (Figure 35 A,C).

Second segment with first pair of elytrophores, long ventral buccal cirri, similar to tentacular cirri, and biramous parapodia; notopodium short, digitiform, with bundle of long, finely spinous, capillary notosetae; neuropodium larger, subcorneal, with anteroventral bract; upper and middle neurosetae long, finely spinous, with capillary tips; lower ones short, with widely spaced spines tapering to fine tips (Figure 35D–F). Distal border of extended pharynx with 13 pairs of papillae, middorsal and midventral ones on wide lobulated bases, middorsal one extra long and tapered (extending from mouth when pharynx partially extended), midventral one about 2 times longer than lateral papillae, about one-fourth as long as middorsal one. Two pairs of strong hooked jaws, each with 7–10 lateral teeth.

Third segment with first pair of dorsal cirri, with short cirrophores and styles extending slightly beyond neuropodia; notopodia short, digitiform, with small bundle of long notosetae; neuropodium with upper and lower neurosetae similar, lanceolate, spinous; middle row of neurosetae short, acicular, terminating in fine spines and aristae (Figure 35G–J). Following few parapodia similar, with few notosetae on fourth and fifth notopodia, lacking from segment 6 on. Cirrigerous parapodium of segment 8 with notopodium larger, rounded; upper neurosetae short, curved, with larger spines basally and close-set spines distally, similar to lower group of neurosetae; middle acicular neurosetae aristate, with subdistal spines along one side (Figure 35K–M; Fauvel, 1932, fig. 7b,c).

Beginning with segment 9, notopodium wide, rounded, flattened, anterodorsal to upper half of neuropodium, with notoaciculum and spinning glands; neuropodium with conical presetal acicular lobe, short upper anterior bract under notopodium, anteroventral bract, and truncate postsetal lobe; three groups of neurosetae: lower group numerous, within anteroventral bract, curved, with large spines basally, fine spines distally, tapering to capillary tips; middle row (4–6 in number) stout, acicular, hairy distally and subdistally along one side, with or without aristae; upper group, emerging from low anterodorsal bract, of 2 types: (a) longer, fewer (up to 8 in number), slender, with brush-like tips; (b) short, more numerous, with widely spaced spines and fine tips (Figures 35N,O, 36A–E; Fauvel, 1932, fig. 7a). Dorsal cirri short, subulate; ventral cirri short, subulate; ventral cirri short, tapered (Figure 36B). Without parapodial branchiae.

TUBE.—According to Fauvel (1932:39), the tubes were felt-like, secreted by the spinning glands and coated with mud.

ETYMOLOGY.—The species is named for the well-known polychaete worker, Pierre Fauvel.

DISTRIBUTION.—Arabian Sea and Bay of Bengal. In 60 to 1480 meters.