Odontaster setosus Verrill 1899

Odontaster setosus Verrill

Odontaster setosus Verrill, 1899:207, pl. 29: figs. 1–1c, 2; 1915: 120.

This five-armed stellate or pentagono-stellate species is generally smaller than O. hispidus. The round-topped dorsal plates bear 10–25 long, fine spinules. The papular pores are in six well-defined areas, a small circular area in the center of the disc, and five large papularia extending from near the central area to the base of the arms. The dorsal plates in these areas are larger and higher than the other dorsal plates. The superomarginal plates encroach quite far onto the dorsal surface but are not confined to it. They are rectangular, broader than long, and the odd interradial marginal is not differentiated from the others. The edges of the plates are not beveled and the sutures between them are shallow. Several pairs of superomarginals near the tip of the arm may be in contact dorsally. The inferomarginal plates are similar and both series are clothed densely with fine spinules. The large actinal interradial areas are filled with rounded plates in regular rows, at least one of which extends more than two thirds the length of the arm. They are clothed with moderately long setose spinules.

The adambulacral plates are square and bear a furrow series of 5 or 4 stout, blunt, divergent spines; the actinal edge of the plate bears 5 or 6 long, acute spines, and between the two series are 3–5 spines similar to those of the furrow series. The small mouth plates bear a cluster of small preoral spines, about five larger lateral spines, two pairs of stout epioral spines, and a very large, heavy, hyalinetipped, unpaired, recurved spine. The madreporite is small, round, channeled, closer to the center of the disc than the margin, and surrounded by a few enlarged dorsal plates.

Verrill states that this species is often taken with O. hispidus. I am inclined to the view that, although their ranges overlap, essentially O. hispidus is a northern species, while O. setosus is more southern.

MATERIAL EXAMINED.–Oregon Station 272 (1) [R=28 mm, r=12 mm, Rr=1:2.3]. Combat Station 185 (1) [R=23 mm, r=14 mm, Rr=1:1.9].

The Goniasteridae have a large disc and large marginals. The actinal and abactinal plates are usually tessellate. Papulae are confined to the dorsal surface, usually single, and in a circumscribed area. The tube feet, in two rows, have large suckers. There is no large recurved spine on the mouth plates. The actinal interradial areas are extensive. The interbrachial septa are membranous.

The Goniasteridae of the North Atlantic have undergone a recent extensive revision by Dr. Jerald A. Halpern1. The section here on this family is mainly a paraphrase of parts of this very excellent monograph, done with the kind permission and assistance of Dr. Halpern.

Goniaster Agassiz

Goniaster L. Agassiz, 1835b:441. [Type, by original designation, Asterias tessellatus Lamarck.]

Phaneraster Perrier, 1894:388. [Type, by original designation, Pentagonaster semilunatus Linck.]

Only one species, Goniaster tessellatus (Lamarck), is known from the western Atlantic.