Cladiella variabilis

Cladiella variabilis (Tixier-Durivault, 1944) (Figs. 54C, 59 & 60) Lobularia variabilis Tixier-Durivault, 1944c: 478; Tixier-Durivault 1948: 50–54, Figs. 37–42. Material examined. Syntypes. MNHN-IK-2000-395. Red Sea. 1850, coll. M. Clot Bey; MNHN-IK-2015-2017, same details as MNHN-IK-2000-395. Description. Syntype MNHN-IK-2000-395 is an encrusting colony with a maximum cross-section of 64 x 52 mm (Fig. 54C). Its densely placed flattened lobes are arranged in groups with empty spaces between them. The retracted polyps appear as small pits on the lobe surface. The sclerome of the polyps comprises various platelets, mostly with a lateral constriction including some figure-eights, 0.05–0.06 mm long (Fig. 59A). The surface of these sclerites displaces a combination of a tuberculate and a cristate texture. Some platelets have an elevated circumferential rim, producing a central depression on their surface. The sclerites of the surface layer of the lobes comprise poorly developed dumbbells, 0.05–0.08 mm long, with rounded tubercles (Fig. 59B). The dumbbells from the interior of the lobes are 0.07–0.08 mm long. Their tubercles are mostly pointed conical, separated by a bare waist, 0.02–0.03 mm wide and 0.01–0.02 mm long (Fig. 59C). The surface of the base of the colony comprises poorly developed dumbbells, 0.06–0.09 mm long, featuring rounded tubercles (Fig. 60A). The dumbbells from the interior of the colony base are 0.07–0.09 mm long, mostly with blunt-ended conical tubercles separated by a bare waist, 0.02–0.03 mm wide, and 0.01–0.02 mm long (Fig. 60B). Color. The dry syntype MNHN-IK-2000-395 is beige. Remarks. The initial species assignment of L. variabilis (Tixier-Durivault 1944c: 478) did not depict the morphological characters of the syntype colony. They were subsequently presented in the revision of the genus (Tixier-Durivault 1948: 50–54, Figs. 37–42). This species features relatively short dumbbells in the interior of the colony base (0.09 mm), and densely placed surface tubercles. In general, the current examination of both the syntype colony morphology and its sclerites corresponds to the amended description by Tixier-Durivault (1948). Syntype MNHN-IK-2015-2017 (not shown) resembles the other syntype, except for its size. No details are provided regarding the exact locality in the Red Sea where the syntypes were collected. Distribution. Red Sea.