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“Eunoe spica, n. sp.
Materials. Weddell Sea, in 513-650 m: Station 68-1 (paratype at Allan Hancock Foundation); 69-1 (holotype, USNM 46582).
Description. The holotype is in two pieces. The anterior end of 12 segments is 4.2 mm long, and the posterior tapering end of 18 segments is 10 mm long. The dorsum is overlain by large projecting notosetae in whorled series. The prostomium is ivory white, the eyes are black, and the dorsum is pale. Elytra have a weak reticulated pattern. The prostomium is quadrate, its frontal peaks at anteroectal margins. Their bases are widely separated by the base of the median antenna. Paired antennae are much smaller than the median one and are inserted ventrally; each has a short base and a tapering style about half as long as the prostomium. Each of the four eyes is large and circular; the anterior pair is at the sides, slightly in front of midlength of the lobe, and the posterior eyes are at postectal margins. Palpi, antennae, and tentacular cirri are smooth.
The first elytra are subovate; others are larger and broader and excavate at anterior margins. The upper surface has dispersed microtubercles, and the margin is smooth (Figure 6a); each is simple and slightly curved and ends in a blunt tip (Figure 6b). The inner edge of each elytrum has a series of about seven long tapering yellow macrospines resembling those of Harmothoe impar grandispina Annenkova [1937, p. 1521 from the northern Sea of Japan, but the latter has bifid neurosetae and thus is a species of Harmothoe.
The first tentacular segment is dorsally reduced to a pair of long dorsal and ventral cirri. Their styles exceed the palpi in length; each base has a few thick embedded setae, some projecting between the bases of the cirri. The second segment is larger and complete across the dorsum, forming a short transverse collar across the posterior end of the prostomium. It bears the first pair of elytrophores.
Typical parapodia are biramous, with notopodia and neuropodia widely separated (Figure 6c). Each has characteristic kinds of setae and attenuated acicular lobes from which the long spinelike aciculum projects. Neurosetae range from being thick, long, vaguely serrated at the cutting edge, and closely spaced denticles in transverse rows to being much thinner and more coarsely serrated at the cutting edge. The largest setae are in the middle of the fascicle, and the smallest are superiormost.
Neurosetae are much more slender, the largest being about a third as thick as the largest notosetae. The inferiormost (Figure 6e) are similar but shorter. All are distally entire; one or two at the upper end of the series may show an obscure accessory tooth. The cutting edge is crossed by transverse rows of serra‑ tions in which the distalmost serration is a large blunt tooth. Serrations diminish basally (Figure 6d)”