Crispatotrochus rugosus Cairns, 1995

Kitahara, Marcelo V. & Cairns, Stephen D., 2008, New records of the genus Crispatotrochus (Scleractinia; Caryophylliidae) from New Caledonia, with description of a new species, Zootaxa 1940 (1), pp. 59-68 : 64-65

Crispatotrochus rugosus Cairns, 1995

Plate 1 , figs. E, H–J, M, S

Crispatotrochus rugosus Cairns, 1995: 57 , pl. 13, figs. a–b. — Cairns and Zibrowius, 1997: 104. — Cairns, 1998: 363, 368, 378. —Cairns, 1999: 77, figs. 6 a–b. — Cairns et al. 1999: 21. — Cairns, 2004: 265 .

Material examined. Bathus 3 station DW 838, 1 (MNHN-Scl.2008-0042); Norfolk 2 stations DW 2024, 5 (MNHN-Scl.2008-0043 [4], USNM 1115430 [1]), DW 2117, 2 (MNHN-Scl.2008-0044 [1], USNM 1115429 [1]), DW 2150, 1 (MNHN-Scl.2008-0045).

Description. Corallum ceratoid, elongate, usually curved, and slightly flared distally. Two specimens attached to an older coralla near the calicular margin. Pedicel robust and massive (PD:GCD = 0.32–0.45), expanding to a thin encrusting base. Largest specimen examined 15.1 x 13.3 mm in calicular diameter and 29 mm in height. Calice slightly elliptical (GCD:LCD = 1.05–1.1), and serrated, however, smallest specimen 4.4 x 4 mm in calicular diameter displays a hexagonal calicular margin with each corner corresponding to each S1. Theca covered with thin transverse ridges, which are more prominent near base. Well preserved coralla bear slightly ridged costae (C1–4) separated by very thin shallow striae. One specimen analysed has C4 broader than C3, which in turn is broader than C1–2. Corallum white, but a specimen from Norfolk 2 DW 2150 has C–1 and upper edges of S1–2 pigmented brown.

Septa hexamerally arranged in four complete cycles according to formula: S1>S2>S3>S4. S1 highly exsert (up to 3 mm), thicker than higher septal cycles, with rounded upper margin, and vertical sinuous axial edges almost reaching columella. S2 less exsert, about four fifths width of S1, and have very sinuous axial edges. The sinuosity of secondaries starts above the sinuosity of the primaries. S3 equal to slightly less exsert, but wider and more sinuous than S4. Usually the sinuosity of tertiaries starts above sinuosity of secondaries. Upper outer edges of S4 fuse to the adjacent S1 or S2, becoming more exsert than S3.

Fossa of moderate depth containing a columella composed of 3–5 slender twisted elements.

Remarks. Only reported from the Pacific Ocean, and grouping with the species with septa hexamerally arranged in four complete cycles ( C. cornu , C. curvatus , C. galapagensis , C. inortatus , C. irregularis , and C. septumdentatus ), C. rugosus is easily distinguished by the presence of transverse ridged theca and the absence of septal teeth in the lower axial septal margin of S1. Among the new records presented herein, one lot (DW 2024, composed of 5 specimens collection number) contains a specimen without twisted elements in the columella. Also in the same lot, two specimens are attached near the calicular margin of dead coralla of the same species, being both curved 90º, with the calices staying in the same orientation as the older coralla. Both older coralla encrusted with bryozoans, barnacles, polychaetes, and stylasterids (?).

Another specimen examined (DW 2150 collection number), displays S1–2 and outer edge of S3, and their corresponding costae (only near calicular margin) dark brown pigmented, the costal pigmentation being less dark, similar to two specimens from NZOI Stn C527, examined by Cairns (1995).

Type locality. Lord Howe Seamount Chain (26º59.7’S, 159º18.9’E), 376 m.

Type specimens. The holotype (NZOI H–625), and the paratypes (NZOI P–1014 [1], NZOI P–1015 [2]) are deposited at the New Zealand Oceanographic Institution, Wellington, and the paratypes (USNM 94124 [1] and USNM 94125 [19]) are deposited at the National Museum of Natural History , Washington D.C .

Distribution. New Caledonia: from 23º00.81’S, 166º55.87’E to 23º28’S, 167º51’E, 245– 402 m. Elsewhere: Wallis and Futuna – Combe and Field Banks; Vanuatu – Tanna, Efaté, Epi, and Espiritu Santo; Australia – off Cape Leveque (western Australia); Philippines – Verde Island Passage; Malaysia – Sabah (Celebes Sea); Kermadec Islands; Lord Howe Seamount Chain; 142– 616 m.

Figures

PLATE 1. Crispatotrochus rubescens (A–D, F–G): A—calicular view X 1.6, B—oblique calicular view X 1.6, C— detail of columella X 3.5, and D—lateral view X 0.7 of USNM 1115428; F—calicular estereo pair X 2.4, and G—lateral view X 1, of MNHN-Scl.2008-0041. Crispatotrochus rugosus (E, H–J, M, S): E—oblique calicular view showing septal exsertnes X 2.8, H—calicular estereo pair X 3.1, I—lateral view X 1.9, and J— lateral view of same specimen showing the attachment near calicular edge of older coralla X 0.9, of USNM 1115430, M—lateral view X 1.9, and S—lateral view showing septal and costal pigmentation X 1.1, of MNHN-Scl.2008-0043. Crispatotrochus septumdentatus (K–L, N–R): K—calicular estereo pair of holotype (MNHN-Scl.2008-0046) X 3.7, L—oblique calicular view of holotype X 3.7, N— calicular view of paratype (USNM 1115444) X 3.7, O—calicular view of paratype X 4.6, P, Q, R—lateral views of paratypes (P and Q), and holotype (R), X 1.4, 1.5, 2.1 respectively.