Myxoderma platyacanthum, (H. L. CLARK, 1913)

Mah, Christopher, 2007, Phylogeny of the Zoroasteridae (Zorocallina; Forcipulatida): evolutionary events in deep-sea Asteroidea displaying Palaeozoic features, Zoological Journal of the Linnean Society 150 (1), pp. 177-210 : 192

MYXODERMA PLATYACANTHUM (H.L. CLARK, 1913)

(W/SYNONYM SSP. RHOMALEUM FISHER, 1919)

Zoroaster platyacanthus H.L. Clark, 1913: 199 .

Myxoderma platyacanthum Fisher, 1919a: 392 ; H.L. Clark, 1920: 99; 1923: 152; Fisher, 1928: 52; Alton, 1966: 1709; Aziz & Jangoux, 1984: 193; Maluf, 1988: 44, 124; Lissner & Hart, 1993: 109; Clark & Mah, 2001: 231.

Myxoderma platyacanthum rhomaleum Fisher, 1919a: 393 ; 1928: 45, 54, pl. 14, fig. 3.3a, pl. 15, fig. 2; pl. 16, fig. 1; pl. 23, fig. 1; pl. 24, fig. 2; pl. 25, fig. 3.

Occurrence: Queen Charlotte Island ( Canada), Oregon, Californa to Mexico, 256–2904 m.

Material: British Columbia ( Canada): CASIZ 8636 , Queen Charlotte Islands : Moresby Island, 2904 m on grey mud, 52°39.00′30.00″N, 132.00°38.00′0.00″W, Coll. 3.ix.1890. (19 wet specs. R = 6.0, r = 0.9; R = 7.2, r = 1.1; R = 7.5, r = 0.9; R = 6.3, r = 0.9; R = 5.3, r = 0.8; R = 6.3, r = 0.8; R = 5.9, r = 1.0; R = 4.6, r = 0.8; R = 5.7, r = 0.9; R = 4.9, r = 0.7; R = 6.3, r = 0.8; R = 3.1, r = 0.6; R = 5.9, r = 0.8; R = 5.4, r = 0.6; R = 6.3, r = 0.8; R = 5.9, r = 0.8; R = 4.8, r = 0.8; R = 6.5, r = 0.8; R = 6.2, r = 1.0) Oregon : NMNH E10355, SW of mouth of Columbia River , 46°0.1′N, 124°50.8′W. 549 m, Coll. 9.v.1963. (1 dry spec. R = 6.1, r = 1.3 cm) ; NMNH E16027, SW of mouth of Columbia River , 46°0.0′N, 124°47′W, 410 m, Coll. 25.i.1963 (1 dry spec. R = 7.6, r = 1.4) ; NMNH E10354, SW of mouth of Columbia River , 46°0.0′N, 124°58.8′W, 503 m, Coll. 14.v.1963 (1 dry spec. R = 2.9, r = 1.8) . NMNH E16031 , Winchester Bay 43°46′N, 124°57′W, 507 m, Coll. 19.x.1888. [3 dry specs. R = 7.6, r = 1.3, R = 8.0, r = 1.1, R = 6.6, r = 1.3 (arm tips broken)] Washington : NMNH E10353 , Astoria Canyon , 46°13.6′N, 124°44.2′W, 1006 m, Coll. 13.iii.1963. (1 dry spec. R = 4.2, r = 1.2) California : CASIZ 115924 Eel Canyon , Humboldt County, 704 m, on mud, Coll. xii.1966 (6 wet specs. R = 5.0, r = 1.0, R = 4.2, r = 0.6, R = 4.1, r = 0.8, R = 5.9, r = 1.1, R = 5.6, r = 1.1 R = 6.1, r = 0.9) CASIZ 115900 Gulf of Farallones , 37°26.70′N 123°1.30′W, 519–660 m, Coll. 18.xii.1985 (2 wet specs. R = 5.4, r = 0.9; R = 5.1, r = 0.9) ; CASIZ 115911 Gulf of Farallones , 37°35.30′N 123°14.50′W, 1491− 1405 m, Coll. 14.xii.1985 [2 wet specs. R = 4.4, r = 0.8, R = 5.4, r = 1.0 (arm tips broken)] ; CASIZ 115908 Santa Barbara Channel to Santa Cruz Island 91–366 m (2 wet specs. R = 2.9, r = 0.5, R = 3.4, r = 0.6) ; CASIZ 115920 Off San Luis Obsipo County, 35°1.80′N 121°10.20′W, 576 m, Coll. 7.ix.1976 (1 wet spec. R = 5.7, r = 1.3). Mexico : NMNH 31640 San Pablo Point , Baja California. 27°7.8′N, 114°33.10′W, 519 m, Coll. 15.iii.1911 (1 dry spec. R = 6.7, 0.95 cm) . SIO E 249 S of Isla San Pedro, Mexico. 27°40′N, 111°29.6′W to 27°32.1′N, 111°20.1′W. 931–952.0 m. Coll. 16.i.1961. [3 wet specs. R = 7.2 r = 1.0, R = 7.9 r = 1.0, R = 7.7 r = 0.8 (arms broken)] .