Smithsonian National Museum of Natural History

Original Description
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"Aglaophamus foliosus, new species

(Plate 21)

Records: 5:4 sta. 322 (1 small); 6:7 ?sta. 340 (9 small) ; 15:4 sta. 631 (1, TYPE).

Description: Length of a posteriorly incomplete specimen is 60 mm; width is 7 mm in the anterior fourth of the body and segments number more than 53. The body is depressed and tapers posteriorly. The pro­stomium (Fig. A) is subspherical, flat, with the front margin somewhat crenulated. Frontal antennae are small, cirriform and inserted at the ectal margins. The prostomium is about as wide as long and has a pair of everted nuchal organs at its postectal margins. The ventral paired an­tennae are larger than the frontal ones, and resemble the ventral cirri of the first segment; they are thickest at the base and taper distally. There are no visible marks on the prostomium.

The first segment has large parapodia directed forward so that the long neurosetae extend beyond the prostomial antennae. Its notopodium is a conical lobe with a strong fascicle of camerated capillary setae, and a thick, projecting aciculum ; postacicular setae are represented by a few, very slender delicate capillaries. The first neuropodium is longer, better developed than the notopodium and has a well developed ventral cirrus. The second parapodium is directed laterally; by the third segment the postacicular setae are well developed and longer than the preacicular barred setae. The ventral oral field extends back through six segments.

The dissected proboscis has 14 longitudinal rows of papillae, with 10 to 14 in a row ; they diminish in size orally, and at their basal end they do not furcate into smaller papillae as is typical of some Antarctic spe­cies; the proximal surface of the proboscis is wrinkled or perhaps smooth when extended.

Interramal cirri are involute and first present from segment four; the first are smaller than the attached notopodial lobe, which is broad and foliose. The involute cirri increase in size farther back and form a complete coil at greatest development. Through segments 20 to 36 the superior lobe is foliose but exceeded in size by the broad notopodial lobe. The preacicular lobe is broadly truncate, short and surpassed by the acicular lobe; this is incised at the emergence of the aciculum. The post­acicular lobe is triangular to broadly rounded, not much longer than the acicular lobe and greatly surpassed in size by the superior lobe and the notopodial cirrus. The last is a large, conspicuous, foliose process con­tinuing large throughout; its broad base terminates in an acuminate tip (Fig. B). The interramal cirrus is well developed in anterior and middle segments.

Neuropodia lack an erect lobe. The preacicular lobe is unique in that it has a rounded lobe in superior and inferior positions. The acicular lobe is rounded, largest in its upper part, and the aciculum emerges near its midlength. Postsetal lobes are large, broad, foliaceous, longest in their upper end. The ventral cirrus is tapering and cirriform.

A. foliosus is characterized chiefly by its large notopodial cirrus which is distally acute, by the development of an accessory inferior lobe in the neuropodial presetal lobe, and by the presence of interramal cirri from the fourth segment.

Distribution: South Sandwich Islands, in 1482 m; questionably Falkland Islands, in 578-567 m; and Cape Horn, in 1906-2013 m."

(Hartman, 1967)