Brisinga costata Verrill 1884

Brisinga costata Verrill, 1884

Brisinga costata Verrill, 1884:382; 1885:529; 1894:280; 1895:211.

MERISTICS.—Arms = 12–13, R = 161–381 mm, r = 16–22 mm, R/r = 10–17/1, length of gonadal region = 61–95 mm, length of longest arm spine = 9–15 mm.

DIAGNOSIS.—[80.a] Madreporite large, raised; [100.a] madreporite irregular, coarsely channeled; [110.a,b] abactinal disc plates metapaxillar, tumid, irregular; [120.a] abactinal disc plates widely scattered in membrane; [130.a] abactinal disc plates bearing 1–3 very small sharp spinelets; [170] number of arms 12 or 13; [210.a] abactinal arm plates rod-like; [220.a] abactinal arm plates imbricate across arms in raised ridges (costae), costae well spaced, no plates between or beyond costae; [240.a] abactinal arm plates bearing 0–8 small sharp spinelets in a line on ridge of plate; [280.a] marginal plates very small relative to adambulacrals; [290.a] shape of marginals irregular; [300.b] marginals occurring about every 2–3 adambulacrals; [310.a] marginals bearing one moderately long acicular spine; [320.a] adambulacral plates large relative to marginals, higher than long; [330.b] adambulacrals spool-shaped, higher than long, with sharp inner distal prolongation; [340.a] furrow margin straight; [350] number of furrow spines 1–3; [360.a] furrow spines quite small, slender, acute; [370.a] furrow spines on proximal end of adambulacral; [380] number of subambulacral spines 1(2–3); [390.a,b] subambulacral spines moderately large, acicular, sometimes proximal ones slightly capitate; [420.a] ambulacral plates high, forming distinct ridge along arm; [430.a] head of ambulacrals saddle-shaped; [470.a] structure of tubefeet delicate, thin, translucent; [480.a] mouth plates rather small relative to adambulacrals; [490.a] mouth plates T-shaped; [500] number of preoral spines per mouth plate 1; [510.a] preoral spines very long, fine, acicular; [520.a] position of preoral spines adoral; [530] number of lateral oral spines 2 per mouth plate; [540.a] lateral oral spines small, slender, slightly curved, acicular; [550.a] lateral oral spines on oral edge of mouth plates, beneath preoral spines; [560] number of suboral spines per mouth plate 1; [570.a] suboral spines large, acicular; [580.a] position of suboral spines just behind preorals; [620.a,b,c] pedicellariae tiny, abundant on membrane of disc and in irregular bands on membranous part of arms beyond costae, all spines enclosed in fleshy sacs completely covered with pedicellariae; [630.a] all pedicellariae microscopic.

COLOR.—Unknown.

TYPES.—USNM 7820 (holotype), Albatross Sta 2210, collected 1884 south of Block Island, Rhode Island, 1812 m; USNM 11256 (paratype), Albatross Sta 2533, SE of George's Bank, 1514 m.

MATERIAL EXAMINED.—Holotype and paratype; 1 specimen, USNM 6739, Albatross Sta 2116, off Hatteras, North Carolina, 1624 m; arm fragments, Albatross Sta 2706, off George's Bank, 2173 m; 1 specimen, USNM 18503, Albatross Sta 2116, off Cape Hatteras, North Carolina, 1624 m; arm fragment, R/V Knorr Sta 325, Hudson Canyon, 39°13.3′N, 71°53.4′W, 1974 m; arm fragment, USNM E20942, Oregon Sta 2571, Gulf of Mexico, 26°34′N, 90°31′W, 2377 m; 2 specimens, Pillsbury Sta 1178, Haiti, 19°14′N, 73°14′W, 1903 m; 17 specimens, Pillsbury Sta 748, off Venezuela, 11°24.8′N, 67°10.1′W, 1865 m.

DISTRIBUTION.—Western Atlantic, George's Bank to Venezuela, 1514–2377 m.