Smithsonian National Museum of Natural History

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“Lagisca oculata, new species

(Plate 6)

Record: 8:8 sta. 722 (4, TYPE).

Description: This is a large, broad species; no color pattern remains; all elytra and many cirri have fallen away. One specimen, complete ex­cept for the pygidial processes, measures 43 mm long, 11 mm wide with­out, and 14 mm with, setae; it has 45 segments. Elytral scars are mod­erately large and occur on segments as typical of the genus. The last 9 or 10 segments may be normally left uncovered by scales.

The prostomium is broad (Fig. A), squat, has four black, circular eyes in trapezoidal arrangement; the anterior eyes are in front of the middle and the posterior eyes are near the posterior margin of the lobe. Prostomial peaks are small but distinct, and have acute tips. The median antennal base is thick and robust; it extends back to divide the prosto­mium to its posterior base. Paired antennae have slenderer bases, be­neath the prostomium; antennal styles are lacking. The paired palpi are prolonged, cirriform, and smooth; they extend distally well beyond other parts (styles of the first dorsal cirri are missing).

The first parapodia are reduced; they project forward at the sides of the prostomium ; each has long dorsal and ventral cirrophores and thick projecting acicular setae in sparse numbers. The second segment is the first with normal setae and elytral scars. Normal parapodia are broadly biramous, have conspicuous notopodial fascicle with setae in spreading series (Fig. B). Neuropodia are longer and directed laterally; their setae are in parallel series. The acicular lobe is attenuate and the aciculum projects distally from its end; a small slender lobe extends be‑yond the acicular tip. Notosetae are thicker than neurosetae; each is acicular, distally entire and conspicuously spinous along its free length (Fig. C). Neurosetae are much slenderer, distally pointed or slightly falcate and also spinous along their free length (Fig. D); their tips are weakly bifid, with a minute secondary tooth (Fig. E). A pair of nephrid­ial papillae occurs at the ventral base of neuropodia; each is long and cylindrical (Fig. B).

Lagisca oculata differs from other species of the genus in its un­usually broad prostomium which is medially divided; neurosetae termi­nate distally in a tapering tip and a minute secondary tooth; all neuro­setae are of one kind.

Distribution: South Georgia, in 3138-3239 m.”

(Hartman, 1967)