Amphiophiura bullata ( Thomson, 1877 )

Stöhr, Sabine & O’Hara, Timothy D., 2021, Deep-sea Ophiuroidea (Echinodermata) from the Danish Galathea II Expedition 1950 - 52, with taxonomic revisions, Zootaxa 4963 (3), pp. 505-529 : 516-518

Amphiophiura bullata ( Thomson, 1877)

Ophioglypha bullata Thomson, 1877: 399

Amphiophiura bullata — Matsumoto 1915: 77

Amphiophiura bullata bullata — Paterson, 1985: 131

Material examined

EAST ATLANTIC OCEAN • 3 specimens; en route from Monrovia to Takoradi; 00°42’N, 00559’W; 5160 m; 18 Nov 1950; Galathea II stn. 30; clay; NHMD-867153 .

INDIAN OCEAN • 1 specimen; between Cape Town and Durban; 35°00’S, 027°22’E; 4330–4390 m; 21 Jan. 1951; Galathea II stn. 175; Globigerina ooze; NHMD-867164 • 19 specimens; off Port Elizabeth; 23°12’S, 027°35’E; 4350 m; 21 Jan. 1951; Galathea II stn. 176; NHMD-867160 • 15 specimens; between Cape Town and Durban; 35°07’S; 030°35’E; 4470 m; 23 Jan. 1951; Galathea II stn. 178; clay; NHMD-867185 • 2 specimens; between Cape Town and Durban; 34°44’S, 034°16’E; 3800 m; 24 Jan. 1951; Galathea II stn. 179; NHMD-867200 • 4 specimens; 32°33’S, 032°01’E; 3620 m; 31 Jan. 1951; Galathea II stn. 186; Globigerina ooze; NHMD-867203 • 7 specimens; off Durban; 29°42’S, 031°19’E; 2640–2760 m; 03 Mar. 1951; Galathea II stn. 190; Globigerina ooze; NHMD-867231 • 112 specimens; off Durban; 32°00’S, 032°41’E; 3430–3530 m; 05 Feb 1951; Galathea II stn. 192; Globigerina ooze; NHMD-867145 • 22 specimens; off Durban; 32°34’S, 031°52’E; 3680 m; 06 Feb. 1951; Galathea II stn. 193; Globigerina ooze; NHMD-867141 • 60 specimens; off Durban; 34°09’S, 030°45’E; 4360 m; 07 Feb 1951; Galathea II stn. 194; Globigerina ooze; NHMD-867134 • 2 specimens; off Durban; 30°32’S, 034°27’E; 2690–2700; 15 Feb. 1951; Galathea II stn. 198; NHMD-867099 • 3 specimens; Mozambique Channel, N of Madagascar, S of Mayotte; 14°20’S, 045°09’E; 3390–3520 m; 17 Feb. 1951; Galathea II stn. 217; Clay, Globigerina ooze; NHMD-867100. • 48 specimens; between Madagascar and Mombasa; 08°52’S, 049°25’E; 4480–5020 m; 07 Mar. 1951; Galathea II stn. 231; NHMD-867143 • 8 specimens; between Madagascar and Mombasa; 07°24’S, 048°24’E; 4730 m; 09 Mar. 1951; Galathea II stn. 233; Globigerina ooze; NHMD-867140 • 53 specimens; Madagascar to Mombasa; 05°25’S, 047°09’E; 4800–4820 m; 10 Mar. 1951; Galathea II stn. 234; Globigerina ooze; NHMD- 867287 • 100 specimens; between Madagascar and Mombasa; 04°47’S, 046°19’E; 4810 m; 11 Mar. 1951; Galathea II stn. 235; Globigerina ooze; NHMD-305714, NHMD-867258 • 100 specimens; off Kenya; 03°23’S, 044°04’E; 3960–3980 m; Galathea II stn. 238; Globigerina ooze; NHMD-305688, NHMD-867094 • 5 specimens; Maldives to Ceylon; 01°56’N, 077°05’E; 4350 m; 09 Apr. 1951; Galathea II stn. 280; Globigerina ooze; NHMD-867144 • 150 specimens; Sri Lanka; 03°38’N, 078°15’E; 3310 m; 10 Apr. 1951; Galathea II stn. 281; Globigerina ooze; NHMD-867158 • 24 specimens; off Sri Lanka; 05°32’N, 078°41’E; 4040 m; 11 Apr. 1951; Galathea II stn. 282; Blackish mud; NHMD-867172 • 4 specimens; Bay of Bengal; 17°10’N, 084°30’E; 2820 m; 24 Apr. 1951; Galathea II stn. 299; Mud; NHMD-868679 • 6 specimens; Sunda Trench; 09°49’S, 114°13’E; 3810–3840 m; 11 Sep. 1951; Galathea II stn. 474; NHMD-868364 .

KERMADEC TRENCH • 1 specimen; 36°31’S, 178°38’E; depth 4410 m; 24 Feb. 1952; Galathea II stn. 663; brown sandy clay with pumice; NHMD-868419 • 20 specimens; 36°34’S, 178°57’W; 4540 m; 25 Feb. 1952; Galathea II stn. 664; brown sandy clay with pumice; NHMD-868443.

TASMAN SEA • 3 specimens; 31°27’S, 153°33’E; 4090–4530 m; 12 Nov. 1951; Galathea II stn. 550; very stiff clay; NHMD-868416 • 1 specimen; 39°45’S, 138°42’E; 4670 m; 18 Dec. 1951; Galathea II stn. 574; NHMD- 868417.

Remarks

The A. bullata species complex currently includes four accepted subspecies ( A. bullata bullata , A. bullata convexa ( Lyman, 1878) , A. bullata vitjazi Litvinova, 1971 , A. bullata pacifica Litvinova, 1971 ), as proposed by Paterson (1985). The main morphological difference between the first three subspecies is in the dorsal disc plating, with A. bullata convexa having mostly large primary plates and radial shields with few or no small scales, A. bullata bullata having some scales and A. bullata vitjazi having many scales and only slightly larger primary plates. Their variability in disc plating overlaps though, as previous authors have remarked ( Paterson 1985). Christodoulou et al. (2019) included nine specimens of Amphiophiura bullata from around the world with the three different disc morphologies defined by Paterson ( A. convexa , A. bullata and A. vitjazi ) and their analysis suggested at least two clades, A. bullata and A. convexa , which correlate with different geographic areas. Most of the Galathea specimens of A. bullata are morphologically similar to A. bullata convexa , e.g., all Indian Ocean samples ( Fig. 3A, B ), except from off Durban, but there is geographic overlap with specimens that are more similar to A. bullata bullata ( Table 2 ), which leads us to conclude that morphology is plastic and of low taxonomic value in this species complex. We propose to reserve the name A. bullata for Atlantic, Indian and Southern Ocean populations and A. convexa for the North Pacific clade, based on the respective type localities and the genetic clades, and raised to species level. We consider A. bullata pacifica conspecific with A. convexa . The taxonomic status of A. bullata vitjazi remains to be resolved.

Figures

FIGURE 3. A, B Amphiophiura bullata, Galathea II stn. 234, NHMD-867287 A, dorsal disc, B. ventral disc. C, D, Ophiuroglypha irrorata concreta, Galathea II stn. 238, NHMD-867376, C, dorsal disc, D, ventral disc. DS, disc scale, OS, oral shield, PP, primary plates, RS, radial shield, VAP, ventral arm plate. Scale bars = 1 mm.