Stephanocyathus (Odontocyathus) campaniformis (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

Stephanocyathus (Odontocyathus) campaniformis (von Marenzeller, 1904)

Fig. 5G-I

Stephanotrochus campaniformis von Marenzeller, 1904a: 302, pl. 18, figs 20, 20A.

Stephanocyathus campaniformis . -Gardiner and Waugh 1938: 189, 191. - Zibrowius 1980: 103. - Zibrowius and Gili 1990: 32-35, pl. 4, figs A-F, pl. 5, figs E-J

Stephanocyathus (Odontocyathus) campaniformis . - Cairns and Keller 1993: 243, fig. 5A, B.

Type locality.

Off Walvis Ridge, Namibia (SS ' Valdivia ' stn. 83: 25°25'03"S, 6°12'04"E); 981 m (von Marenzeller 1904a).

Type material.

Two syntypes are deposited at the ZMB ( Zibrowius and Gili 1990).

Material examined.

SAM_H3178 (1 specimen): Eastern margin, 39 km from Coffee Bay/ 31 km off Hluleka Estuary, 32°00'42.00"S, 29°33'00.00"E; 1420 m.

Description.

Corallum highly variable in shape, ranging from flat, cylindrical, bulbous, to bowl-shaped (as in the examined specimen) with rounded base. BD smaller than CD, and having a basal scar indicating point of attachment. Calice slightly elliptical (GCD:LCD = 1.1), with serrated calicular margin. Only specimen examined 29.8 × 27.5 mm in CD, 24.3 in BD, and 12.6 mm in H. Lower costae unevenly sized and spaced, with C1-2 prominent and extending from calicular margin to base, where they bear basal tubercles. C3-5 equal, separated by fine striae, and less distinct towards base. All costae covered with fine granules. Corallum white.

Septa hexamerally arranged in five cycles, the last cycle being incomplete, according to the formula: S1-2> S3> S4> S5 (≤ 80 septa). S1-2 highly exsert, and extend to columella with straight axial margins. Each S1-2 bears a palus separated from its respective septum by a deep notch. P1 fuse to columella. S3 less exsert and ¾ the width of S1-2, with a straight axial margin, and separated from respective P3 by a notch. When flanked by S4, S3 and S4 join deeper in fossa, meeting columella as one septum. S4 less exsert, ½ the width of S3, with straight to slightly dentate axial margins. S5 equally exsert as surrounding S4, but rudimentary in development. Septal faces covered with fine granules. Pali variable in size and shape. Fossa relatively shallow, but reported to be deep in larger specimens. An under-developed papillose columella present, usually a result of pali fusing.

Distribution.

Regional: Eastern margin of South Africa, off Coffee Bay; 1420 m. Elsewhere: Madagascar Plateau ( Cairns and Keller 1993); Walvis Ridge (off Namibia) ( Zibrowius and Gili 1990); 882-1610 m.

Remarks.

Among the Atlantic extant species of Stephanocyathus (Odontocyathus) , S. campaniformis closely resembles S. nobilis (Moseley, 1873), but differs in having a considerably smaller adult size (7.5-11.5 mm) compared with that reported for S. nobilis (10.0-15.0) ( Cairns and Keller 1993; Zibrowius and Gili 1990), and a higher H:GCD ratio (0.4-1.3) unlike that of S. nobilis (0.4-0.8 mm) ( Cairns and Keller 1993; Zibrowius and Gili 1990). The resemblance of the Indian and Atlantic Ocean S. campaniformis representatives has been historically noted ( Cairns and Keller 1993), and specimens reported herein add no taxonomic knowledge to this discussion. Specimens examined herein represent a new South African record, thus extending the Indian Ocean records from the Madagascar Plateau further southwards.

Figures

Figure 5. A, F Stephanocyathus (Acinocyathus) explanans: A, C (USNM 62500, off Durban, 183 - 220 m) Calicular view B basal view C lateral view D, F (SAMC _ A 090144, off Port St Johns, 96 - 98 m) D calicular view E basal view F lateral view G, I Stephanocyathus (Odontocyathus) campaniformis (SAM _ H 3178, off Coffee Bay, 1420 m) G calicular view H basal view I lateral view J, L Stephanocyathus (Odontocyathus) nobilis (SAM _ H 1697, off Groot Berg Estuary, 1050 m) J calicular view K basal view L lateral view M, N Tethocyathus virgatus (SAMC _ A 073180, off Mazeppa Bay, 240 - 250 m) M calicular view N lateral view O, P Trochocyathus (Trochocyathus) sp. 1 (SAM _ H 1244, off East London, 59 m) O calicular view P lateral view. Scale bars: 10 mm.