Sinularia tessieri n. sp.

(Figs 8-11; 16F, G)

TYPE MATERIAL. — Holotype: ZMTAU Co 34502 and 4 microscope slides, Saint-Leu, Récif Pointe au Sel (Cimetière) (21°11’26.29”S, 55°16’59.27”E), reef slope, 16-20 m, 11.IV.2008.

Paratype: RMNH Coel 40120, same data as holotype.

TYPE LOCALITY. — Reunion, Saint-Leu, Récif Pointe au Sel (Cimetière).

DISTRIBUTION. — So far known only from the type locality.

ETYMOLOGY. — The species is named after Dr Emmanuel Tessier, Manager, Association Parc marin de La Réunion, in appreciation of his initiative to conduct the octocoral survey in Reunion and his support during the field work and afterwards.

DESCRIPTION

Holotype: an encrusting colony, with maximum cross-section of 7 × 4 cm and height up to 4 cm (Fig. 8A). Polyparium consisting of short lobes and a few longer ones that may branch off once. Lobes and lobules mostly flattened, or occasionally knob-shaped, and in part tending to bend down towards each other. Colony with a hard texture.

Polyps with tentacle rods and some collaret and point sclerites (Fig. 9 A-C). Tentacle rods up to 0.08 mm long (Fig. 9A). Point sclerites with poorly developed club-heads and up to 0.17 mm long (Fig. 9B). Collaret consisting of spindles, the longer ones slightly bent, up to 0.20 mm long (Fig. 9C).

Surface layer of the lobules containing clubs with warty heads and tubercles on handle, 0.07-0.16 mm long (Fig. 9D) and with a few crosses (Fig. 9E). In addition with spindles, up to 0.26 mm long, mostly with simple or, less commonly, complex tubercles (Fig. 9F).

Surface layer of base of colony containing clubs, similar to those of lobules, but wider, 0.10-0.20 mm long (Fig. 10A). Also spindles, up to 0.26 mm long (Fig. 10B).

Interior of the lobules with branched stout spindles, up to 2.70 mm long (Fig. 11A), with complex tubercles (Fig. 11B), or with simple ones (Fig. 11C). Interior of base with slightly longer spindles, occasionally branched, up to 3.30 mm long (Fig. 11D), with complex tubercles (Fig. 11E).

Colour

Preserved holotype dark brown, almost black.

Living features

The colony is light-grey in colour, expanded polyps are light-beige.

VARIABILITY

Paratype RMNH Coel 40120 differs in size of colony: maximum cross section 6 × 5 cm and hight of up to 2 cm (Fig. 8B).

REMARKS

Sinularia tessieri n. sp. belongs to Sinularia clade 2 of McFadden et al. (2009): polyps with collaret, points and tentacle rods; clubs with an indistinct central wart. Both the holotype and paratype are encrusting (i.e. lack a stalk). The previously described three species ( S. parva Tixier-Durivault, 1970, S. muqeblae Verseveldt & Benayahu, 1983 and S. soongi Benayahu & Van Ofwegen, 2011) with encrusting growth form in this clade have distinctly longer and differently-shaped clubs on the surface of their lobules than in S. tessieri n. sp. In S. parva the clubs are up to 0.30 mm and some are even 0.40 mm long (see Verseveldt 1980). Similarly, S. muqeblae has clubs up to 0.32 mm, with narrow head, and a more slender and pointed handle compared to those of S. tessieri n. sp. The recently described S. soongi, which also belongs to Sinularia clade 2, features clubs up to 0.25 mm long. Moreover, the stalked species of that clade differ from S. tessieri n. sp. Sinularia grandilobata Verseveldt, 1980 has clubs up to 0.10 mm long compared to up to 0.17 mm in the newly-described species. The clubs of S. capricornis Dautova, Van Ofwegen & Savinkin, 2010 are up to 0.18 mm long and the species features un-branched spindles in the interior of the lobes, as opposed to the stout and heavily branched ones of S. tessieri n. sp. (Fig. 11A). Notably, the latter stout spindles of S. tessieri n. sp. are not found in any of the species of clade 2. It is thus concluded that S. tessieri n. sp. differs from all previously-described species of clade 2.