Flabellum (Flabellum) politum Cairns, 1989a

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

Flabellum (Flabellum) politum Cairns, 1989a

Fig. 11I, J

Flabellum pavoninum paripavoninum . - Yabe and Eguchi 1942a: 91-93 (in part: 'Soyo Maru’ Stn. 419, pl. 5, fig. 8A-C) . - Yabe and Eguchi 1942b: 129-130 (in part: pl. 11, fig. 9A-C).

Flabellum (Flabellum) politum Cairns, 1989a: 53-54, pl. 28, figs A-F. - Cairns 1989b: 67. -Cairns 1994: 73, pl. 32, figs A-C. - Cairns and Zibrowius 1997: 153-154. - Cairns 1998: 394. - Cairns et al. 1999: 31. -Cairns 2004a: 303. - Cairns 2009: 18. - Kitahara and Cairns 2021: 186-188, figs 91E-H, 93.

Flabellum sp. 1. - Cairns 1989b: 63, 77.

Type locality.

Samar Sea, Philippines (12°13'15"N, 124°05'03"E); 216 m ( Cairns 1989a).

Type material.

The holotype and fourteen paratypes are deposited at the NMNH ( Cairns 1989a, 1994).

Material examined.

DEFF_NANSEN- INV 34 (5 specimens): Eastern margin, 32 km from Shaka’s Rock / 16 km off Nhlabane Estuary, 29°43'11.99"S, 31°25'47.99"E; 184 m. DEFF_NANSEN-INV 96 (2 specimens): Eastern margin, 32 km from Richards Bay / 91 km off Bulungulu Estuary, 28°40'47.99"S, 32°23'59.99"E; 20 m. SAMC_A090160 (5 specimens): Eastern margin, 10 km from Shaka’s Rock / Mhlali Estuary, 29°30'00.00"S, 31°20'23.99"E; 53-54 m.

Description.

Corallum flabellate, unattached, and bearing a narrow circular pedicel. Calice compressed (GCD:LCD = 2.1-2.4), with a smooth calicular margin. Largest specimen examined (SAMC_A090160) 38.9 × 16.4 mm in CD, 30.8 mm in H, and 1.3 mm in PD. Thecal faces planar and diverging in an angle between 50-70°. Angle of thecal edge (excluding crest) between 124-150°, thecal crest rounded. Corallum white with reddish brown stripes corresponding to septa, usually porcelaneous.

Septa arranged in six complete cycles according to the formula: S1-3 > S4 > S5 > S6, sometimes pairs of S7 present (≤ 194 septa). S1-3 equidistant, and joining columella with moderately sinuous axial margins. S1-3 upper distal edge notched. S4 ~ ¼ the size of S1-3, sometimes joining columella with sinuous axial margin. S5 ½ the size of S4. S6 rudimentary. S7, if present, also rudimentary. Septa faces with spines arranged perpendicular to septal margin. Fossa deep, narrow, with a rudimentary columella.

Distribution.

Regional: Eastern margin of South Africa, off Shaka’s Rock extending towards Richards Bay; 20-185 m. Elsewhere: Philippines; Indonesia ( Cairns and Zibrowius 1997); South China Sea; Japan ( Cairns 1989a); New Caledonia ( Kitahara and Cairns 2021); Australia (Cairns 2004a); 40-717 m.

Remarks.

These specimens represent new records of Flabellum (F.) politum in the southwestern Indian Ocean and illustrate that it may be found in shallower waters. It is also worth noting that adult F. politum can be easily mistaken for juvenile Flabellum (F.) pavoninum " Flabellum coalitum " form ( Cairns and Zibrowius 1997), but may be distinguished by its smooth and porcelaneous thecal face. A full comparison of F. politum and other species can be found in Cairns (1989b).

Figures

Figure 11. A Tubastraea sp. cf. Tubastraea diaphana (SAM _ H 5103, Cape Vidal, 59 m) A lateral view B Tubastraea micranthus (ORI _ EIb 3, locality data unknown) B full view C, D Flabellum (Flabellum) leptoconus (ORI _ DIIa 1, Port St. Johns, 409 - 440 m) C calicular view D lateral view E, H Flabellum (Flabellum) pavoninum E, F (SAMC _ A 073135, off Coffee Bay, 250 - 280 m) E calicular view F lateral view G, H (SAM _ H 4582, off Shaka's Rock, 150 m) G calicular view H lateral view I, J Flabellum (Flabellum) politum (SAMC _ A 090160, off Shaka's Rock, 53 - 57 m) I calicular view J lateral view K, L Flabellum (Ulocyathus) alabastrum (SAMC _ A 090102, off the Agulhas, 168 m) K calicular view L lateral view M, N Flabellum (Ulocyathus) lowekeyesi (SAM _ H 1695, off Kosi Bay Estuary, 720 - 780 m) M calicular view N lateral view O, P Javania antarctica (SAMC _ A 090150, off Gouritsmond, 333 m) O calicular view P lateral view. Scale bars: 10 mm.