Balanophyllia S.V. Wood, 1844

Lam, Katherine, Morton, Brian & Hodgson, Paul, 2008, Ahermatypic corals (Scleractinia: Dendrophylliidae, Oculinidae and Rhizangiidae) recorded from submarine caves in Hong Kong, Journal of Natural History 42 (9 - 12), pp. 729-747 : 730-731

Genus Balanophyllia S.V. Wood, 1844

Balanophyllia eguchii Wells, 1982

( Figure 1A–B )

Balanophyllia eguchii Wells, 1982:211–212 , Figs 1 , 4 , 5 and 6, holotype Balanophyllia eguchii Wells, 1983:239 , Plate 14, Figs 6–8; Cairns 1991:23, Figs 9h–j, holotype; Ogawa et al. 1998:147, Plate 2, Figs 4 , 5, Plate 4, Figs 3 , 4

Description

Solitary or reptoid colonial, forming clusters of short corallites by extra-tentacular budding from a basal coenosteum, the new polyps eventually becoming isolated and solitary. Secondary buds are rare. Thick corallite walls are cylindrical in younger individuals but compressed in adults and up to, 6.4 mm and 5 mm in longer and shorter diameters, respectively. The lightly-spined costae extend 3–4 mm below the calice rim. Septa vary in number from 36 (4 mm in diameter) in small corallites to as many as 80 in large ones.

Septa are hexamerally arranged in four cycles. Ventral and dorsal septa are in five cycles. Total number of septa depends on calice size. The larger the calicular diameter, the greater the number of septa. At a calicular diameter of 4 mm there are 36 septa; 5.5–7 mm, 48 septa; 10 mm, 64 septa and the largest calice of 13.5 mm in diameter had 80 septa ( Cairns 1991). In Hong Kong, calicular diameter is generally 4–6 mm.

In 48-septa corallites, S 1 and S 2 are equal in size, only slightly exsert, and have straight, vertical inner edges and are laciniate deep in the fossa. S3 rudimentary and pairs of S 4 meet before the S 3 and extend to the columella but do not form paliform lobes. Inner edges of fused S 4 also laciniate. Fossa deep and elongate. Columella rudimentary, composed of small crispate elements attached to the lowest inner edges of the larger septa.

The colour of the polyps varies geographically. Individuals from Hong Kong are orange, those from Japan, Hawaii, Bay of Panama and the Galápagos Islands are orange-brown, pinkish-orange, yellow and pinkish-vermilion, respectively.

Type locality

North side of Marchena Island, Galapagos, 6 m.

Distribution

Galápagos (1–27 m) ( Cairns 1991), Japan, Hawaii, off Queensland, Australia, Gulf of Panama, Malpelo (7–85 m) ( Wells 1982), Conic Island Cave in Hong Kong (this study).

Figures

Figure 1. Balanophyllia sp. and Dendrophyllia sp. A–B, calicular (longer diameter56.5 mm) and side view of four solitary corallites of B. eguchii (maximum height59.02 mm); C–D, calicular (longer diameter514.9 mm) and top view of a B. ponderosa colony (height531.3 mm); E–G, calicular (longer diameter57.8 mm) and side views of two colonies of D. arbuscula (colony size of F and G535.1 mm and 40.1 mm, respectively); H–I, top and side views of a small D. arbuscula colony (height518.2); J–L, calicular (longer diameter511.7 mm) and top views of two colonies of D. ehrenbergiana (height of K and L513 mm and 19.8 mm, respectively); M–N, calicular (longer diameter513.4 mm) and side view of a colony of D. coccinea (height527 mm); O–P, calicular (longer diameter58 mm) and side view of colony of D. compressa (height533.1 mm); Q–R, calicular (longer diameter59.9 mm) and four solitary corallites of D. gracilis (maximum height521.2 mm).

Figure 3. Tubastrea diaphana collected from Conic Island cave being grazed by three individuals of Aeolidiella sp. The white area of the skeleton is the grazed area. One Aeolidiella is on the top of the colony, the second is on the bottom and the third one was dislodged during collection.

Figure 4. Cyathelia sp., Culicia sp. and Oulangia sp. A–B, calicular (longer diameter55.1 mm) and colony of Cyathelia axillaris (height535.85 mm); C, calicular of Culicia japonica (longer diameter55.9 mm); D, caliculars of Culicia rubeola (colony size515.3 mm×14 mm) and E, calicular of Oulangia stokesiana (longer diameter59 mm).