Eupanthalis elongata (Treadwell 1931)

Eupanthalis elongata (Treadwell, 1931)

Iphionella elongata Treadwell, 1931:315, fig. 2a–d.

Eupolyodontes elongata.—Hartman, 1938b:125, fig. 41 a–d; 1959:82, 111.

Eupanthalis kinbergi.—Strelzov, 1972:303, figs. 3D.12A–F, 13A–G [part]. [Not Eupanthalis kinbergi Mcintosh, 1876.]

MATERIAL EXAMINED.—PHILIPPINE ISLANDS: Marinduque Island, off Tayabas Light, 52–291 m, Albatross sta, 24 Feb 1909, holotype of Iphionella elongata (USNM 19544).

TYPE MATERIAL.—The holotype is an anterior fragment of 46+ segments, 40+ mm long, and 10 mm wide with setae; the pharynx is completely extended. It was previously examined by Hartman (1938b).

DESCRIPTION.—Elytra oval, delicate, transparent, attached eccentrically to elytrophores, leaving middorsum uncovered (Figure 15C).

Prostomium oval, with rather deep longitudinal groove, with 2 pairs of lateral eyes, anterior pair much larger than posterior pair; lateral antennae on short ceratophores attached to anterior margin of prostomium, with styles more than 2 times length of prostomium; palps stout, long, tapered, smooth (Figure 15A; Treadwell, 1931, fig. 2a; Hartman, 1938b, fig. 41a; Strelzov, 1972, fig. 12A). Tentacular segment distinct dorsally with tentaculophores lateral to prostomium, without setae; dorsal and ventral tentacular cirri subequal in length, longer and stouter than lateral antennae (Figure 15A; Strelzov, 1972, fig. 12A).

Notopodium of segment 2 small, rounded, acicular lobe on anterodorsal side of larger truncate neuropodium, without notosetae; ventral buccal cirri similar to tentacular cirri, longer than following ventral cirri; neurosetae all same type, stout, tapering to fine hairy tips (Figure 15D,E; Strelzov, 1972, fig. 12B). Distal border of extended pharynx with 13 pairs of papillae, middorsal one lobulated, on wide base, midventral one split and irregularly papillate, on wide base, neither one extra long; 2 pairs of dark hooked jaws, each with 4 or 5 lateral teeth (Figure 15B).

Parapodia of segments 3–8 with small rounded notopodia, without notosetae, as on 2nd parapodia; dorsal cirri on segments 3, 6, and 8 with short cirrophores on posterodorsal sides of notopodia, with styles tapered, extending beyond setae; upper group of neurosetae slender, lanceolate, spinous; middle acicular neurosetae stout, with slightly hooked tips with distal spines and hairy aristae; lower neurosetae slender, slightly curved, lanceolate, spinous (Figure 15F–J).

Notopodia from segment 9 wide, rounded, flattened, on anterodorsal half of larger neuropodia, with spinning glands (Figure 16A,F). Upper group of numerous neurosetae of 2 types: (a) wider basally, tapering to fine tips, with close-set spinous rows (Figure 16Ba); (b) shorter, with whorls of widely spaced spines (Figure 16Bb); middle stout acicular neurosetae with slightly hooked hairy tips, with or without hairy aristae, with subdistal spines along one side (Figure 16C,G; Treadwell, 1931, fig. 2c; Hartman, 1938b, fig. 41c); numerous lower neurosetae similar to anterior ones (Figure 16D,H). Dorsal cirri with wide short cirrophores with styles not extending beyond setae (Figure 16E). No distinct branchial vesicles except for somewhat inflated thin-walled areas on body.

DISTRIBUTION.—Philippine Islands, Gulf of Tonkin. In 27 to 291 meters.