Cladiella echinata ( Tixier-Durivault, 1941 )

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 : 26

Cladiella echinata ( Tixier-Durivault, 1941)

Figs. 2F , 13 & 14

Lobularia echinata Tixier-Durivault, 1941: 575–582 , Figs. 1–6 ; Tixier-Durivault 1948: 117–124, Figs. 110–115.

Material examined. Syntypes. MNHN-IK-2000-28, Perim Is., Yemen, Red Sea, 1891, coll. F. Jousseaume; MNHN- IK-2000-96, same details as MNHN-IK-2000-28 .

Description. Syntype MNHN-IK-2000-28 is part of a stalked colony with densely placed rounded lobes and lobules, 65 mm long and 43 mm wide ( Fig. 2F ).

The sclerome of the polyps comprise sclerites, featuring a rough tuberculate surface texture and an irregular lateral outline, with some constrictions or slits, 0.04–0.06 mm long (Fig. 13A). The sclerites of the lobe surface are poorly developed dumbbells, 0.06–0.07 mm long, featuring rounded tubercles and some blunt-ended conical ones (Fig. 13B). The dumbbells from the lobe interior are 0.07-0.10 mm long, their bare waist is 0.02–0.04 mm wide and 0.01–0.02 mm long (Fig. 13C). Their tubercles are sharp-pointed conical or even spine-like processes, occasionally featuring a divided tip. The poorly developed dumbbells of the base surface are 0.03–0.07 mm long, displaying a variety of shapes including small ones with rounded tubercles and larger ones with pointed conical or blunt-ended tubercles, all mostly with an irregular surface tuberculation ( Fig. 14A ). The sclerites from the interior of the colony base are dumbbells, 0.08-0.12 mm long, their bare waist is 0.03–0.04 mm wide and 0.01–0.02 mm long. Both ends of these dumbbells are ornamented with sharp-pointed conical tubercles that can also present as spine-like processes, occasionally divided at their tip ( Fig. 14B ).

Color. The ethanol-preserved syntype MNHN-IK-2000-28 is light beige-cream.

Remarks. In general, the current morphological findings for syntype MNHN-IK-2000-28 correspond to the original description of L. echinata by Tixier-Durivault (1941). This species is uniquely characterized by its dumbbells ornamented with sharp-pointed conical tubercles and spine-like processes that can be divided at their tip (Figs. 13C & 14B. In some cases, the spiky prominences of the dumbbells leave almost no waist or only a remarkably narrow one. In addition, the tuberculate texture of the irregular polyp sclerites similarly characterizes the species. It should be noted that this species has dumbbells up to 0.12 mm, the longest recorded for the genus, similar to several other congeneric Red Sea types ( Table 2). Among all the Red Sea Cladiella types re-described in the current study, C. echinata is the only one that was collected from the southernmost location, Perim Is., adjacent to Bab al-Mandab Straits, at the entrance to the Red Sea. The other syntype MNHN-IK-2000-96 resembles the former except in size.

Distribution. Perim Is., Yemen.

Figures

FIGURE 1. A–C. Cladiella colonies on the reef flat of Eilat (northern Gulf of Aqaba, Red Sea). Note that Cladiella colonies appear light brown–beige when the polyps are extended and gray when they are retracted.

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 3. Cladiella arbusculoides Verseveldt & Benayahu, 1978, holotype, SMNHTAU_Co_13272. Scanning electron micrographs of colony top sclerites.A. Polyp sclerites.B. Poorly developed dumbbells of the surface layer of lobes.C. Dumbbells from the interior lobes.

FIGURE 4. Cladiella arbusculoides Verseveldt & Benayahu, 1978, holotype, SMNHTAU_Co_13272. Scanning electron micrographs of colony base sclerites. A. Poorly developed dumbbells of the surface layer of base. B. Dumbbells from the interior base.

FIGURE 5. Cladiella bottai (Tixier-Durivault, 1943), holotype, MNHN-IK-2000-25. Scanning electron micrographs of colony top sclerites. A. Polyp sclerites. B. Poorly developed dumbbells of the surface layer of lobes. C. Dumbbells from the interior lobes.

FIGURE 6. Cladiella bottai (Tixier-Durivault, 1943), holotype, MNHN-IK-2000-25. Scanning electron micrographs of dumbbell sclerites from the interior base.

FIGURE 14. Cladiella echinata (Tixier-Durivault, 1941), syntype, MNHN-IK-2000-28. Scanning electron micrographs of the colony base sclerites. A. Poorly developed dumbbells of the surface of the base. B. Dumbbells from the interior of the base.