Ophiactis abyssicola (M. Sars, 1861)

Fig. 26h–j

Amphiura abyssicola Sars, 1861: 18 pl. 2(7–12).

Ophiactis poa Lyman, 1879: 40, pl. 13(356–358). — Lyman, 1882: 119, pl. 20(13–15) [according to Clark, H.L., 1918].

Ophiactis abyssicola . — Lyman, 1882: 122. — Clark, H.L., 1923: 334–335. — Mortensen, 1933b: 347. — Clark, A.M. & Courtman-Stock, 1976: 161. — Olbers et al. 2019: 247–249, fig. 250–251. — O’Hara & Thuy, 2022: 33, fig. 13(c–d).

Ophiactis corallicola Koehler, 1895: 460–461, fig. 5 [according to Clark, H.L., 1918].

Ophiactis echinata Koehler, 1898: 48–49, pl. 5(15–16) [according to Clark, H.L., 1918].

STUDY MATERIAL. — JC066: stn 8-5, Atlantis Bank, 32° 42.862´S, 57° 14.666´E to 32° 43.3´S, 57° 15.2´E, 828–994 m, 10/12/2011: 2 (NHMUK 2025.56) (DNA code= OAB1) .

COMPARATIVE MATERIAL EXAMINED. Ophiactis abyssicola (M. Sars, 1861): AFR239/ A28266, West coast, 33° 9.6´S, 17° 12´E, 455 m, 1/2008, SAMC MB-A88404 (DNA code=A88404). CE13008/91, Whittard Canyon, 48° 38.15´N, 10° 41.4´W, 2400 m, 6/2013, NUI (DNA code=NUI1666E-2). GB 903/2, Gulf of Mexico, central slope, 27° 4.794´N, 92° 48.996´W, 1066–1067 m, 16/7/2016, MV F248373 (DNA code=F248373). Ophiactis cuspidata Lyman, 1879: TAN1402/31, Forde Seamount, Stratum 1, 35° 19.01´S, 170° 27.09´W to 35° 18.48´S, 170° 27.53´W, 1205–1600 m, 11/2/2014, NIWA 95695 (DNA code= NIWA 95695).

Distribution. Arctic (127–1838 m), NE Atlantic (27–2400 [?4813] m), W Atlantic (1054–3465 m), E Atlantic (425–1642 m), S Africa (311–2000 m).

Remarks. The COI sequences from these SWIO Ridge specimens fall into the “abyssicola ” clade of this complex, similar to specimens from the Atlantic and South Africa at bathyal depths (O’Hara et al. 2014). The type series of O. corallicola (Gulf of Gascoyne, 950–1700 m) and O. echinata (Azores, 800 m) and O. poa (Tristan da Cunha, 914–1005 m) fall within the geographic and depth range of this species (as known from COI barcodes) and are here regarded as synonyms. However, Paterson (1985) has also recorded lower bathyal/abyssal specimens from the North Atlantic under this name, which would give it a very extensive bathymetric range. These deeper animals deserve further investigation. Off Australia and New Zealand, the sister species O. cuspidata Lyman, 1879 is restricted to upper bathyal depths and another species O. amator Koehler, 1922b inhabits mid-lower bathyal depths (O’Hara et al. 2014a).