Cladiella michelini (Tixier-Durivault, 1944)

Lazar, Einav, Mcfadden, Catherine S., Huchon, Dorothée & Benayahu, Yehuda, 2025, Redescription of type material of the genus Cladiella Gray, 1869 (Octocorallia, Malacalcyonacea, Cladiellidae) from the Red Sea, Zootaxa 5674 (1), pp. 1-84 : 55-56

Cladiella michelini (Tixier-Durivault, 1944)

( Figs. 28F , 39 & 40 )

Lobularia Michelini Tixier-Durivault, 1944b: 339 ; Tixier-Durivault 1948: 70–75, Figs. 61–66.

NOT Alcyonium digitulatum (partly) Stiasny, 1937: 392.

Material examined. Syntypes. MNHN-IK-2000-388, Red Sea, 1850, coll. H. Michelin ; MNHN-IK-2000-404, Red Sea, 1850, coll. A. B. Clot Bey.

Description. The holotype is a fragment of an encrusting colony with a cross-section of 70 x 52 mm featuring small rounded lobes and lobules arranged in several distinct groups ( Fig. 28F ). The retracted polyps appear as small surface pits on the lobe surface.

The sclerome of the polyps consists of platelets and rods featuring an irregular outline, 0.05–0.06 mm long ( Fig. 39A ). Their surface has a tuberculate texture occasionally associated with a cristate-like one. The surface of the lobes features elongated sclerites, slightly resembling in morphology that of poorly developed dumbbells, 0.07–0.08 mm long, ornamented with densely placed rounded tubercles ( Fig. 39B ). The dumbbells from the interior of the lobes are 0.07–0.09 mm long and ornamented with blunt-ended conical or pointed conical tubercles, separated by a bare waist, 0.02–0.03 mm wide and 0.01–0.03 mm long ( Fig. 39C ). The sclerites of the surface of the colony base are poorly developed dumbbells, 0.06–0.10 mm long featuring rounded or blunt-ended conical tubercles ( Fig. 40A ). The dumbbells from the interior of the colony base are 0.08–0.11 mm long ( Fig. 40B ), their bare waist is 0.02–0.03 mm wide and up to 0.02 mm long, ornamented with pointed conical and blunt-ended conical tubercles.

Color. The dry syntype MNHN-IK-2000-388 is beige-brown.

Remarks. The initial species assignment of L. michelini by Tixier-Durivault (1944b: 339) did not depict the morphological characters of the syntype colony. They were subsequently presented in the revision of the genus ( Tixier-Durivault 1948: 70–75, Figs. 61–66). This species is characterized by the elongated sclerites of the surface layer of the lobes and the surface of the colony base and sparse occurrence of dumbbells. The current findings for both the colony morphology and its sclerites correspond to the amended description by Tixier-Durivault (1948). Although the caption to Figure 66 in that publication refers to the lobe sclerites, the images H–J of that figure correspond to the polyp sclerites also depicted in the current study ( Fig. 39A ). Syntype MNHN-IK-2000-404 (not shown) resembles the other syntype, except for its size. No details are provided on the exact locality in the Red Sea where the type colony was collected.

Distribution. Red Sea.

Figures

FIGURE 28. Images of Cladiella type colonies. A. Cladiella irregularis (Tixier-Durivault, 1944), syntype MNHN-IK-2000- 384. B. Cladiella kükenthali (Tixier-Durivault, 1942), holotype, MNHN-IK-2000-385. C. Cladiella laciniosa (Tixier-Durivault, 1944), syntype, MNHN-IK-2000-386. D. Cladiella letourneuxi (Tixier-Durivault, 1944), syntype, MNHN-IK-2000-31. E. Cladiella lineata (Tixier-Durivault, 1944), holotype MNHN-IK-2000-387. F. Cladiella michelini (Tixier-Durivault, 1944), syntype, MNHN-IK-2000-388.

FIGURE 39. Cladiella michelini (Tixier-Durivault, 1944), syntype, MNHN-IK-2000-388. Scanning electron micrographs of sclerites of the colony top. A. Polyp sclerites. B. Poorly developed dumbbells of the surface layer of the lobes. C. Dumbbells from the interior of the lobes.

FIGURE 40. Cladiella michelini (Tixier-Durivault, 1944), syntype, MNHN-IK-2000-388. Scanning electron micrographs of colony base sclerites. A. Poorly developed dumbbells of the surface of the base. B. Dumbbells from the interior of the base.