Euplexaura sp. a

(Figs. 2 e, 19–20)

Material: RMNH Coel. 38779, one colony, Kharku Island, 29º 20' 51.1" N, 50º 21' 17.7" E, depth 18–20 m, 31 March 2007, coll. K. Samimi Namin; RMNH Coel. 38780 one colony, off Kuwait, Koninklijke Shell Exploratie en produktie laboratorium, sta. T1570, coll. A.J. Keij, 1966.

Description of RMNH Coel. 38779. The Kharku specimen is 8 cm high and 5.5 cm wide (Fig. 2 e). The colony is branched in one plane with cylindrical branches. Calyces not present or very low dome-shaped. A number of winged oysters and echinoderms are attached to the colony.

The polyps have points with flattened spindles, up to 0.25 mm long (Fig. 19 a). Sometimes a few horizontally placed sclerites are present in a polyp but a real collaret was not observed.

The surface layer of the coenenchyme has blunt ellipsoids and spindles, up to 0.25 mm long, with complex tubercles (Fig. 19 c–d). Several of them with one side less tuberculate. The calyces have spindles with smaller tubercles (Fig. 19 b).

The interior has small spindles and rods, up to 0.15 mm long (Fig. 19 e).

Colour. Alive, RMNH Coel. 38779 was white, preserved it is also white. Sclerites are colourless.

Variability. RMNH Coel. 38780 is a larger colony but the sclerites resemble those of RMNH Coel. 38779 (Fig. 20); only the subsurface spindles and rods are slightly different (see Fig. 19 e and Fig. 20 e).

Remarks. This species also has rather big sclerites for a species of Euplexaura, it differs from E. rhipidalis and E. plana in having cylindrical branches, somewhat smaller surface sclerites, and differently shaped subsurface ones. Many species of Euplexaura resemble the present material, because of inadequate descriptions it is to date impossible to identify the colonies to hand.