Cladiella crassa (Tixier-Durivault, 1943)

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 : 19-22

Cladiella crassa (Tixier-Durivault, 1943)

( Figs. 2D , 9 & 10 )

Lobularia crassa Tixier-Durivault, 1943a: 441 ; Tixier-Durivault 1948: 83–88, Figs. 76–81.

Material examined. Syntypes. MNHN-IK-2000-377, Red Sea, 1850, coll. A. B. Clot Bey; MNHN-IK-2015-510; MNHN-IK-2015-2013 (6 fragments), same details as MNHN-IK-2000-377 .

Description. The encrusting lobate syntype MNHN-IK-2000-377 is an encrusting colony with a maximum cross-section of 45 x 25 mm ( Fig. 2D ). The small dark pits on the surface of the densely placed lobes indicate the location of the retractile polyps.

The sclerome of the polyps comprises platelets and rods, 0.04–0.07 mm long, featuring a lateral median constriction, including a few figure-eights ( Fig. 9A ). Their surface is characterized by a cristate texture. The poorly developed dumbbells of the lobe surface are 0.07-0.08 mm long and ornamented at either end with distinct blunt-ended conical tubercles and occasionally rounded ones ( Fig. 9B ). The dumbbells from the lobe interior are 0.08–0.09 mm long with similar blunt-ended conical tubercles at either end and occasionally some pointed conical tubercles ( Fig. 9C ). Their waist is 0.02–0.04 mm wide and 0.01–0.02 mm long. The sclerites of the surface layer of the colony base comprise poorly developed dumbbells, 0.06–0.10 mm long, featuring densely placed rounded or blunt-ended conical tubercles ( Fig. 10A ). The dumbbells from the interior of the colony base are 0.10–0.11 mm long, their waist is 0.02–0.04 mm wide and 0.01–0.02 mm long ( Fig. 10B ). They feature spaced blunt-ended conical and a few pointed conical tubercles. Some of the spaced blunt-ended tubercles of the dumbbells from both the interior of the lobes and the base have a nearly rectangular outline.

Color. The dry syntype MNHN-IK-2000-377 is light brown-beige.

Remarks. The initial species assignment of L. crassa by Tixier-Durivault (1943a: 441) did not depict its morphological characters. Subsequently, they were presented in a revision of the genus ( Tixier-Durivault 1948: 83– 88, Figs. 76–81). In general, the current morphological examination of syntype MNHN-IK-2000-377 corresponds to the description by Tixier-Durivault (1948). That revision noted an additional six colonies currently labelled as syntype MNHN-IK-2015-2013 (not shown) which correspond to syntype MNHN-IK-2000-377, except in size. It should be noted that the description by Tixier-Durivault (1948: Fig. 81) did not differentiate between the polyp and the lobe sclerites, although both were illustrated and correctly referred to in the text. The dumbbell-length, up to 0.11 mm, and their tubercles, which are spaced and ornamented with a nearly rectangular outline, are suggested to be diagnostic for the species. No information is given in the original description regarding the precise collection site of the syntype material in the Red Sea.

Distribution. Red Sea.

Figures

FIGURE 2. Images of Cladiella type colonies.A. Cladiella arbusculoides Verseveldt & Benayahu, 1978, holotype, SMNHTAU_ Co_13272. B. Cladiella bottai (Tixier-Durivault, 1943), holotype, MNHN-IK-2000-25. C. Cladiella brachyclados (Ehrenberg, 1834), syntype, ZMB Cni 303. D. Cladiella crassa (Tixier-Durivault, 1943), syntype, MNHN-IK-2000-377. E. Cladiella dollfusi (Tixier-Durivault, 1943), syntype, MNHN-IK-2000-378. F. Cladiella echinata (Tixier-Durivault, 1941), syntype, MNHN-IK- 2000-28.

FIGURE 9. Cladiella crassa (Tixier-Durivault, 1943), syntype, MNHN-IK-2000-377. 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 10. Cladiella crassa (Tixier-Durivault, 1943), syntype, MNHN-IK-2000-377. Scanning electron micrographs of colony base sclerites. A. Poorly developed dumbbells of the surface layer of the base. B. Dumbbells from the interior of the base.