Caryophyllia kellerae, n. sp. Figs. 2 H–I, 8 Description. The corallum is ceratoid, straight, and attached, the holotype measuring 14.7 x 13.4 mm in CD, 35 mm in height, and 4.2 mm in PD (broken); larger coralla attain a GCD of 16 mm and a PD of 4.8 mm. The PD:GCD ranges from 0.29–0.39. The calice is slightly elliptical (GCD:LCD = 1.08–1.20), and the calicular margin relatively even, consisting of a series of uniformly tall (0.8–0.9 mm), isosceles-shaped triangles. Costae are poorly defined, low, and bear low granules; the theca and entire corallum are white. Septa are hexamerally arranged in four complete cycles (48 septa) according to the formula: S1–2>S4≥S3. As mentioned above, S1–2 are only slightly exsert (0.8–0.9 mm) and have straight to slightly sinuous axial edges that reach 0.8–0.85 the distance to the columella. S3 are equally exsert and have moderately sinuous axial edges that reach about 0.65–0.70 the distance to the columella. At least one, if not both, S4 within each system is as wide if not wider than the S3 within that half-system, ranging from 0.70—0.75 the distance to the columella. The septal faces are uniplanar (not undulating) and covered with rather low granules, which are never aligned in rows or ridges. The 12 P3 form a well-defined elliptical crown, each palus about 1.3 mm wide and having moderately sinuous edges. In one specimen many of the pali had divided in half, appearing as two pali per S3. The fossa is of moderate depth, containing the palar crown and a fascicular columella, consisting of 20–25 slender twisted elements. Remarks. When Caryophyllia kellerae is run through the key of all 66 living species in the genus (Kitahara et al. 2010), it comes closest to C. laevigata Kitahara, Cairns & Miller, 2010, both species having four cycles of hexamerally arranged septa and S4 that are as wide or wider than their S3. But C. laevigata differs in having a dense, brown-colored theca, S1–2 that are more exsert than their S3–4, less columellar elements, and a smaller corallum. Also, it is known only from off New Caledonia (Kitahara, Cairns & Miller 2010). C. kellerae also shows a striking resemblance to C. huinayensis Cairns et al., 2005, known from the closely adjacent southern fjords of Chile but from slightly shallower water (16–256 m); C. huinayensis differs only in having wider S3 than S4 and in having a smaller corallum. Distribution. Continental shelf off Cabo Blanco, Argentina, 310 m, and from geological cores (age unknown) taken at 1161 m depth south of Cape Horn (Fig. 8). Material/ Types: Holotype: WH 311/66, USNM 83398; Paratypes: WH 311/66, 6, USNM 1193277; Vema 15– 121, 258 cm in core, 1, USNM 1130262; Ve m a 15–121, 280 cm in core, 1, USNM 1130260. Type locality. 47°01’S, 60°43’W (continental shelf off Cabo Blanco, Argentina), 310 m. Etymology. Named in honor of Natalia B. Keller, for her many contributions to the taxonomy and ecology of deep-water Scleractinia (see Keller 2011).

Published as part of Cairns, Stephen D. & Polonio, Virginia, 2013, New records of deep-water Scleractinia off Argentina and the Falkland Islands in Zootaxa 3691 (1), DOI: 10.11646/zootaxa.3691.1.2, http://zenodo.org/record/222205