Ophiomyces grandis Lyman, 1879

Ophiomyces grandis Lyman, 1879 View in CoL

Fig. 19g –k View FIGURE 19 , 21i View FIGURE 21

Ophiomyces grandis Lyman, 1879: 46–47 View in CoL , pl. 14(383–385). — Lyman, 1882: 241–242, pl. 19(13–15). — Paterson, 1985: 75–76, fig. 31 (in part). — O’Hara, 1990: 302–303, fig. 2k.

Non Ophiomyces grandis View in CoL . — Cherbonnier, 1965: 846, fig g–k. — Paterson, 1985: 75–76 (in part). — Litvinova, 2001: 147–148, fig. 2–3. — Ordines et al. 2019: 1819–1821, fig. 2 [= Ophiomyces peresi Reys, 1961 View in CoL ].

STUDY MATERIAL. — MD208 : stn CP4913, Walters shoal, Plaine Sud, 33° 48.82´S, 44° 5.9699´E to 33° 51.8´S, 44° 4.72´E, 1539–1615 m, 11/5/2017: 1 ( MNHN IE.2016.1377) GoogleMaps . — MD208 : stn CP4914, Walters shoal, Plaine Sud, 33° 51.1´S, 44° 4.8999´E to 33° 54.73´S, 44° 3.2199´E, 1598–1714 m, 11/5/2017: 4 ( MNHN IE.2016.1372) ( DNA code= IE.2016.1372) GoogleMaps .

COMPARATIVE MATERIAL EXAMINED. Ophiomyces delata Koehler, 1904 : BIOPAPUA/CP3639, Sud de Lae , Golfe de Huon, 7° 23´S, 147° 35´E, 900–932 m, 23/8/2010 GoogleMaps , MNHN IE.2023.4070 ( DNA code=BP34). in2022_ v08/143, Cocos (Keeling), 12° 13.526´S, 96° 57.5957´E GoogleMaps to 12° 14.351´S, 96° 58.2647´E, 1113–1343 m, 17/10/2022, identified by O’Hara (2024b), MV F307642 ( DNA code=F307642). IN2022 _ V09 /116, Site :038, 23° 9.354´S, 112° 48.3609´E, 992 m, 9/12/2022 GoogleMaps , MV F310378 ( DNA code=F310378). Ophiomyces grandis Lyman, 1879 : Challenger / 135E, Tristan d’Acunha, 37° 21´S, 12° 22.5´W, 1828 m, 18/10/1873, holotype GoogleMaps , NHMUK 1882.12 About NHMUK .23.291. IN2018 _ V06 /007, Deep west of Pedra, 44° 20.844´S, 146° 56.82´E GoogleMaps to 44° 22.596´S, 146° 56.76´E, 1745 m, 24/11/2018, MV F272372 ( DNA code=F272372). TAN0307/31, Campbell Plateau , 49° 19.56´S, 176° 33.12´E GoogleMaps to 49° 19.62´S, 176° 32.32´E, 1522–1552 m, 21/4/2003, NIWA 48457 (14). TAN0307/85, Bollons Seamount , 49° 48.69´S, 176° 33.5´W, 1266 m, 2/5/2003 GoogleMaps , NIWA 48621.

COMPARATIVE MATERIAL NOT EXAMINED. Ophiomyces peresi Reys, 1961 : INTEMARES-A22B_ 0718/20, Ses Olives seamount, 38° 56.1´N, 1° 57.97´E, 275 m, 7/2018, identified by Ordines et al. 2019 as Ophiomyces grandis, CFM 7020-7022 ( DNA code= MK934137 View Materials ).

Distribution. SE Australia ( 1000–1840 m); Campbell Plateau/Bollons Seamount ( 1266–1522 m); Tristan da Cunha ( 1828 m), Walters Shoal (1539–1714).

Remarks. Ophiomyces grandis ( type locality Tristan da Cunha) is a southern hemisphere mid-bathyal ( 1000– 1840 m) species, found on seamounts, and is characterised by having only the most distal oral papillae widened at the tip like hockey sticks and up to 3 tentacle scales on the ventral arm plates and several on the lateral arm plates ( O’Hara 1990). The MD 208 specimens measure up to 7 mm dd, and have dimorphic arm spines, with the 4 lowest pointed and as long as the segment and the upper 5–6 short and needle-like. Unlike in the genera Ophiotholia and Ophiohelus , there are no parasol-shaped arm spines. The vertebrae ( Fig. 19k View FIGURE 19 ) have pronounced vertical zygocondyles and a small reduced zygosphene. The LAPs ( Fig. 19g –h View FIGURE 19 ) have a long ventral extension that meets on the mid-radius and separates the VAPs ( Fig. 19j View FIGURE 19 ). The arm spine articulations consist of two convex lips orientated vertically, the arm spines themselves ( Fig. 19i View FIGURE 19 ) have a pronounced groove along their length. The living colour is an off-white ( Fig. 6f View FIGURE 6 ).

Ophiomyces grandis has also been reported from the North Atlantic in 124–802 m ( Cherbonnier 1965; Paterson 1985; Ordines et al. 2019). The latter study supplies the only DNA sequence ( MK934137 View Materials , COI) available from this region, which is distinct from the southern hemisphere O. grandis . This, and the shallower bathymetric distribution of the North Atlantic specimens ( 124–802 m), suggests that it represents a separate species for which the name Ophiomyces peresi Reys, 1961 ( Type locality: Gorringe Bank, North of Madeira, 200 m) is available.