Clathria (Microciona) spinosa ( Wilson, 1902 )

Gómez, Patricia, 2014, The genus Clathria from the Gulf of Mexico and Mexican Caribbean, with redescription and resurrection of Clathria carteri (Poecilosclerida: Microcionidae), Zootaxa 3790 (1), pp. 51-85 : 69

Clathria (Microciona) spinosa ( Wilson, 1902)

( Fig. 13–14 , 20 D, Tab. 4 )

Microciona spinosa Wilson, 1902:396 , Wiedenmayer 1977:141.

Axociella spinosa sensu de Laubenfels 1936a:113.

Clathria (Microciona) spinosa sensu van Soest 1984:959, Zea 1987:167, Hooper 1996:225.

Material examined. CNPGG −072 Serpientes reef Yucatan 21º26’ 22.29N 90º28’25.39”W, 13/VI/2011, 14 m depth. CNPGG −1181 and CNPGG −1190 Madagascar reef Yucatan, 21º26’16.6”N 90º16’39”W, 7/VI/2011, 9– 10.5 m depth. CNPGG −1186 Madagascar reef Yucatan, 21º26’17”N 90º16’38.2”W, 8/VI/2011, 9 m depth.

Description. Massively incrusting sponge 15 cm long, 9 cm wide, 5–6 cm in thickness, covering a gorgonian stem ( Fig.13 A); sample CNPGG–1190 is adhered to a scleractinian 10 cm long, 5 cm wide, 1–3 cm thick. Out of water it expels some kind of mucus and is easily torn. It is bright orange in vivo turning to red upon dying, fading to beige in spirit. It is stiff in consistency when alive, has a coarse conulose surface by means of spiny bumps up to 5 mm round and from less than 1 mm up to 2 mm high. Oscula not seen.

Skeleton. ( Fig. 13 B) The choanosomal skeleton is made up of dendritic fibers that anastomose here and there. These fibers 300–450 µm in diameter are cored by thick styles and subtylostyles, scarcely echinated at the same time. Single fibers measure 130–220 µm, closely beset with spine-like radiating processes at the surface due to fiber endings in tufts.

Spicules. ( Fig. 14 A–F) Subtylostyles straight and slender 169–330 × 1.6–4.9 µm; thick styles with smooth heads, sometimes very minutely spined 131.5–366 × 5.2–18 µm; palmate isochelae 13–16.3 µm; toxa I wing shaped 13–31.2 µm; toxa II lightly oxhorn shaped 45.7–65 µm; large oxea tending to toxiform 286–390 × 1.6 µm (Measurements in Tab. 4 ).

Remarks. There is no difference between the thin incrustation of the original description and the massive incrustation; both shapes have the same irregular skeletal arrangement with dendritic columns irregularly anastomosed, but chiefly composed of dendritic tracts. Spiculation is also within the size range of that recorded by Wilson (1902) and Zea (1987).

Clathria (M.) spinosa can be compared with C. (M.) echinata since they share similar skeletal architecture, spiny surface and spiculation composition. However C. (M.) spinosa is more spiny, lacks the presence of cleistochelae, and the spicules are smaller, particularly the megascleres, toxiform oxeote and palmate isochelae.

Distribution. Yucatan 9–10 m, Mexico. Other locations: West Florida 15 m; Puerto Rico; West Bahamas 10 m; Curaçao 2–4 m; Colombia 6– 9 m.

Figures

FIGURE 13. Clathria (Microciona) spinosa (Alcolado, 1984): A. CNPGG − 1190 Madagascar reef Yucatan. B. Dendritic spongin fiber. Scale bars: A, 2 cm; B, 200 µm.

FIGURE 14. SEM depiction of spicules from Clathria (Microciona) spinosa (Alcolado, 1984): A. Main styles and auxiliary subtylostyles. B. Detail of style II head. C. Detail of auxiliary style I. D. Wing-shaped toxa I and lightly oxhorn toxa II. E. Oxea tending to toxiform. F. Palmate isochelae. Scale bars: A, 50 µm; B, 20 µm; C, D, 5 µm; E, 50 µm; F, 7 µm.

FIGURE 20. Just out of water: A. Clathria (Clathria) foliacea Topsent, 1889 (CNPGG – 1358 Madagascar reef, Yucatan, Mexico. B. Clathria (Clathria) carteri Topsent, 1889 (CNPGG – 1366 Bajos de Sisal reef, Campeche Bank, Mexico). C. Clathria (Microciona) echinata (Alcolado, 1984) (CNPGG – 1409 Progreso, Yucatan). D. Clathria (Microciona) spinosa (Alcolado, 1984) (CNPGG − 1186 Madagascar reef Yucatan). In situ: E. Clathria (Thalysias) venosa (Alcolado, 1984) (CNPGG – 1452 Blanquilla reef Veracruz). Just out of water: F. Clathria (Thalysias) virgultosa (Lamarck, 1814) CNPGG – 1179 Campeche Bank. Scale bars A, B, C, D, F, 2 cm; E, 1 cm.