Leptoseris troglodyta, Hoeksema, Bert W., 2012

Hoeksema, Bert W., 2012, Forever in the dark: the cave-dwelling azooxanthellate reef coral Leptoseris troglodyta sp. n. (Scleractinia, Agariciidae), ZooKeys 228, pp. 21-37 : 22-23

Leptoseris troglodyta sp. n. Figures 1-8

Leptoseris sp. Hoeksemaand Van Ofwegen 2004.

Type material.

Holotype. RMNH Coel. 40138 (1 specimen, dry, Figure 3a), Palau, W of Ulong Island (Rattakadokoru Island), W off barrier reef, 07°18'40"N, 134°13'30"E, Tsey’s tunnel ceiling at 32 m depth, 28 July 2002, coll. B.W. Hoeksema. Paratypes: RMNH Coel. 40139 (15 specimens, dry), same collection data (Figures 2d, 3 b–d).

Other material examined.

Philippines. RMNH Coel. 24187 (3 specimens, dry), RMNH Coel 24195 (36 specimens, dry), Cebu Strait, W of Bohol, NW side of Cabilao Island, 09°53'12"N, 123°45'32"E, vertical wall with caves,10-30 m depth, 7 and 17 November 1999, coll. B.W. Hoeksema (Figures 1a, 2a, 7, 8). RMNH Coel. 40151 (2 specimens, dry), Philippines, Cebu, Mactan Island, Lapu-Lapu City, Marigondo n Cave, 10°15'33"N, 123°59'07"E, ceiling of cave at 25-30 m depth, May 1981, coll. M.B. Best (Figure 6). Indonesia. RMNH Coel. 40152 (7 specimens, dry), Tukang Besi Islands (Wakatobi), Binongko, SW Bay, 05°59'47"S, 124°02'55"E, cave in steep wall 20 m depth, 10 May 2003, coll. B.W. Hoeksema (Figures 2b, 4-5). RMNH Coel. 40150 (25 specimens, ethanol), Tukang Besi Islands (Wakatobi), NE Hoga Island, 05°28'S, 123°47'E, cave in steep reef slope 5 m depth, 12 July 2011, coll. B.W. Hoeksema. RMNH Coel. 40137 (2 specimens, ethanol), North Sulawesi, South of Bunaken Island, Alung Banua village, 01°37'07"N, 124°45'30"E, tunnel in reef wall 17 m depth, 19 December 2008, coll. B.T. Reijnen and S.E.T van der Meij (Figure 2c).

Additional photographic records:

Indonesia, NE Kalimantan, Berau Islands, S of Derawan Island, jetty Derawan Dive Resort, 02°17'03"N, 118°14'49"E, ceiling of caves, 7-10 m deep (4 October 2003; Figure 1b). Papua New Guinea, Off SE point, Misima Island, Pt. Ebola, 6-10 m depth (31 May 1998; Figure 2e). Guam,Blue Hole, 35 m depth (1 June 2000; Figure 2f).

Description.

Corallum attached and solitary or colonial by budding from basal coenosteum (Figures 3-4, 6-8). Calices predominantly monocentric, very thin, cup-shaped to foliaceous, height <15 mm, outline irregularly circular, Ø <30 mm (Figures 1-4, 6-8). They are usually separate from each other above the interconnecting basal plate (Figures 3b, 6, 7), but can also be fused at their margins or lateral sides (Figures 3a, 8b). Corallum wall massive. Costae equal and well defined, with small spiny protuberances (Figures 4a, 7a, 8d). Septa approximately equal in size, with smooth upper edges and parallel ridges (menianes) on their sides (Figures 3, 5, 8). Septal sides may show evenly distributed granulations where menianes are absent (Figures 8 b–c). Columella nearly solid (Figures 3a, 3 c–d, 8 a–b). Living animals azooxanthellate; corals are white, or partly green or red (Figures 1-2), owing to the presence of endolithic algae ( Kühl and Polerecky 2008).

Diagnosis.

Corals cave-dwelling, azooxanthellate. Calices small, cup-shaped, monocentric or fused, forming buds at basal coenosteum.

Etymology.

The epithet troglodyta (noun) means cave dweller in Latin, derived from ancient Greek for "one who dwells in holes".

Distribution.

Records are from coral reefs, usually in areas with limestone outcrops: Indonesia (East Kalimantan, North Sulawesi, Southeast Sulawesi), the central Philippines (Cebu, Bohol), Palau, eastern Papua New Guinea, and the Marianas (Guam) (Figure 9).