Sphenotrochus (Sphenotrochus) aurantiacus von Marenzeller, 1904

Filander, Zoleka N., Kitahara, Marcelo V., Cairns, Stephen D., Sink, Kerry J. & Lombard, Amanda T., 2021, Azooxanthellate Scleractinia (Cnidaria, Anthozoa) from South Africa, ZooKeys 1066, pp. 1-198 : 1

Sphenotrochus (Sphenotrochus) aurantiacus von Marenzeller, 1904

Fig. 15I, J

Sphenotrochus aurantiacus von Marenzeller, 1904a: 280-281, pl. 18, fig. 15. -Wells 1935: 531. - Boshoff 1981: 38-39. - Cairns 1989b: 38. - Cairns 1997: 25.

Sphenotrochus (Sphenotrochus) aurantiacus . - Cairns and Keller 1993: 254-255, fig. 7D, E, G, H.

Type locality.

Agulhas Bank, South Africa (SS ' Valdivia ' stn. 104: 35°16'00"S 22°26'00"E); 115 m (von Marenzeller 1904a).

Type material.

Two syntypes are deposited at the ZMB ( Cairns and Keller 1993).

Material examined.

DEFF_SVMEC-INV346: Southern margin, 96 km from PLETT/ 95 km off Storms Estuary, 34°52'01.38"S, 23°46'17.40"E; 213 m. SAMC_A072997 (1 specimen): Locality data unknown. SAMC_A073073 (1 specimen): Eastern margin, 29 km from Richards Bay / 20 km off Nhlabane Estuary, 28°44'23.99"S, 32°23'12.11"E; 320- 340 m. SAMC_A073145 (2 specimens): Eastern margin, 5 km from Cape Vidal / 16 km off St Lucia Estuary, 28°08'24.00"S, 32°36'24.11"E; 165 m. SAMC_A073160 (1 specimen): Eastern margin, 27 km from Durban / 12 km off Mbokodweni Estuary, 30°04'59.88"S, 31°00'24.11"E; 100 m. SAMC_A073162 (4 specimens): Eastern margin, 19 km from Coffee Bay / 18 km off Mdumbi Estuary, 32°02'53.87"S, 29°19'41.87"E; 250- 280 m. SAMC_A073168 (1 specimen): Southern margin, 37 km from Mazeppa Bay / 18 km off Mendu Estuary, 32°22'48.00"S, 29°00'47.88"E; 450- 500 m. SAMC_A073172 (1 specimen): Eastern margin, 36 km from Coffee Bay / 20 km off Ntlonyane Estuary, 32°18'11.88"S, 29°06'11.88"E; 550 m. SAMC_A073176 (1 specimen): Eastern margin, 35 km from Durban / 26 km off Mbokodweni Estuary, 30°07'59.99"S, 31°03'05.99"E; 150 m. SAMC_A073237 (1 specimen): Southern margin, False Bay ; depth unknown. SAMC_A087450 (1 specimen): Locality data unknown. SAMC_A090082 (3 specimens): Locality data unknown; 106 m. SAM_H817 (1 specimen): Southern margin, 2 km from Mosselbaai / 11 km off Hartenbos Estuary, 34°11'10.12"S, 22°09'40.59"E; 229 m. SAM_H1372 (1 specimen): Eastern margin, 27 km from Mtunzini / 25 km off Matigulu Estuary, 29°10'36.00"S, 31°51'00.00"E; 115 m. SAM_H1385 (1 specimen): Eastern margin, 2 km from Durban / 8 km off Umgeni Estuary, 29°51'59.99"S, 31°00'00.00"E; 101 m. SAM_H1401 (1 specimen): Southern margin, 13 km from East London / 10 km off Ngqenga Estuary, 33°06'44.99"S, 27°55'44.99"E; 79 m. SAM_H1404 (2 specimens): Southern margin, 2 km from Mosselbaai / 11 km off Hartenbos Estuary, 34°11'10.12"S, 22°09'40.59"E; 165- 183 m. SAM_H1409 (3 specimens): Southern margin, 35 km from Port Alfred / 5 km off Mpekweni Estuary, 33°27'59.99"S, 27°12'59.99"E; 97 m. SAM_H1410 (1 specimen): Southern margin, 14 km from Cape Padrone / 26 km off Boknes Estuary, 33°45'59.99"S, 26°18'59.99"E; 90 m. SAM_H1411 (9 specimens): Southern margin, 7 km from East London / 5 km off Buffalo Estuary, 33°02'59.99"S, 27°57'00.00"E; 59 m. SAM_H1416 (1 specimen): Southern margin, 241 km from Agulhas / 247 km off De Mond-Heuningnes Estuary, 36°39'59.99"S, 21°25'59.99"E; 200 m. SAM_H1422 (1 specimen): Southern margin, 6 km from Kidds Beach / 5 km off Ncera Estuary, 33°11'59.99"S, 27°40'59.99"E; 79 m. SAM_H1424 (1 specimen): Southern margin, off East London ; 95 m; SAM_H3197 (1 specimen): Southern margin, 846 km from Port St. Johns / 842 km off Mkweni Estuary, 36°39'59.99" S, 21°25'59.99"E; 366 m. SAM_H3202 (2 specimens): Southern margin, 18 km from Gonubie /off Gqunube Estuary, 29°38'59.99"S, 31°07'59.99"E; 90 m. SAM_H3203 (in part: 2 specimens): Southern margin, 48 km from Kidds Beach / 14 km off Bira Estuary, 33°29'24.00"S, 27°22'59.99"E; 80 m. SAM_H4589 (1 specimen): Eastern margin, 46 km from Port Dunford / 45 km off Nyoni Estuary, 29°19'00.00"S, 32°00'00.00"E; 366 m.

Imagery data.

FAL700 (1 specimen): Southern margin, 24 km from Cape Point/20 km off Sand Estuary, 34°11'06.00"S, 18°38'59.99"E; 44 m.

Description.

Corallum cuneiform, appearing swollen. Base rounded or irregular in shape depending on the substrate. Calice elliptical (GCD:LCD = 1.79-3.7), with calicular margin slightly serrated. Largest specimen examined (SAM_H1372) 7.7 × 2.8 mm in CD, and 13.8 mm in H. Costae smooth, well defined, each composed of a single longitudinal ridge near calicular margin, which overlaps with adjacent costae towards base. Costae sometimes discontinuous at base. Costae arrangement and size correspond to septa. Corallum white and sometimes orange.

Septa hexamerally arranged in four cycles according to the formula: S1 > S2 > S3 > S4 (48 septa). S1-2 highly exsert and bear slightly sinuous axial margins. S3 less exsert, 1/3 smaller than S1-2, and have slightly dentate axial margins. S4 rudimentary. All septal faces bear fine, regularly arranged granules. Columella solid, lamellar, and aligned with S1. Columellar lamellae rise above septa.

Distribution.

Regional: Western to eastern margin of South Africa, off Cape Vidal and extending towards St Lucia; 59-500 m. Elsewhere: No other geographical records are known.

Remarks.

Sphenotrochus (S.) aurantiacus is distinctive from the other two Recent species reported in the region by its: i) solid lamellar columella that rises far above the upper septal margin, ii) in having septa arranged in four cycles (48 septa), and iii) a costa:septa ratio of 1:1.

Figures

Figure 15. A, B Cyathotrochus pileus (SAMC _ A 087424, off Durban, 270 m) A calicular view B lateral view C, D Deltocyathoides orientalis (BIVa 2, locality unknown, 80) C calicular view D basal view E, F Deltocyathoides sentus (USNM 91551, off Shaka's Rock, 300 m) G, H Sphenotrochus (Eusthenotrochus) gilchristi (SAMC _ A 090086, off Cape Point, 24 m) G calicular view H lateral view I, J Sphenotrochus (Sphenotrochus) aurantiacus (SAM _ H 1416, off the Agulhas, 366 m) I calicular view J lateral view K, L Sphenotrochus (Sphenotrochus) evexicostatus (SAMC _ A 090085, locality data unknown, 43 m) K calicular view L lateral view M, N Sphenotrochus (Sphenotrochus) imbricaticostatus (USNM 91715 _ Holotype, off Kosi-Kumpungwini (Sifungwe) Estuary, 44 m) K calicular view L lateral view O, P Tropidocyathus lessonii (SAMC _ A 073218, off Kosi Bay Estuary, 74 m) O calicular view P lateral view. Scale bars: 10 mm (A-H, J-M, O-P); 2 mm (I, N).