Callyspongia (Cladochalina) aerizusa Desqueyroux-Faundez, 1984

Fig. 6

Callyspongia (Cladochalina) aerizusa Desqueyroux-Faundez, 1984: 803, figs 18, 21, pl. 18, pl. 21 figs 157–161.

Material examined

PONTA DO OURO • 1 alcohol preserved fragment of about 4 ×2× 1 cm; Doodle; 26°49′50.408″ S, 32°53′45.97″ E; 18 m deep; 14 Nov. 2015; Cerrano leg.; PdO18a • 2 small fragments, alcohol preserved, about 3×1 × 1 cm; 26°50′36.881″ S 32°53′42.5″ E; Kev’s; 24.1 m deep; 11 Mar. 2017; Cerrano leg.; PO82 • 1 specimen preserved dry, 7× 1× 1 cm; 26°46′55.65″ S, 32°54′13.413″ E; Three Sisters; 24.2 m deep; 14 Mar. 2017; Cerrano leg.; PO86 .

Description

Live sponge erect, cylindrical-tubular (Fig. 6 A–B); the examined specimens are pink (Fig. 6B), pale violet (Fig. 6A) or creamy-white (Fig. 6C). The samples, preserved in alcohol, turn sand-colored, while the dryly preserved sample is creamy-white colored. The surface is strongly conulose (Fig. 6 A–C). The consistence is very tough, elastic and compressible in samples preserved in alcohol, while the dried sample is very firm and uncompressible.

SKELETON. Ectosome (Fig. 6D) formed by reticulation of three sizes of fibers running tangentially: multispicular primary fibers, 40–110 µm in section, forming triangular-polygonal meshes of 490–850 µm in size; pauci-multispicular secondary fibers 15–50 µm and unispicular (at most 3) tertiary fibers, 5–(7.3, 1.8)– 10 µm, forming sub-triangular meshes. Choanosome (Fig. 6E) formed by the reticulation of thick ascending multispicular primary fibers, 60–110 µm in section; the primary fibers are linked

through pauci-multispicular secondary fibers, 20–70 µm, forming quite regular rectangular meshes of 240–360× 220–250 µm in dimensions; presence also of the third size of unispicular fibers, 4–10 µm.

SPICULES. Slender and slightly curved oxeas with acerate and rounded tips (Fig. 6F), 70–(87.5, 8.5)– 95 µm ×2–(4.25, 1.2)– 5 µm.

Remarks

These specimens belong to the subgenus Callyspongia (Cladochalina) Schmidt, 1870 based on the growth form, spiny surface, three sizes of irregular mesh in the ectosome and three sizes of irregular mesh in choanosomal skeleton (Desqueyroux-Faundez & Valentine 2002a).

Hitherto, 27 species are assigned to this subgenus, 19 of which have a distribution in the Indo-Pacific Ocean. The original descriptions of C. (Cladochalina) manus Lendenfeld, 1887, C. (Cladochalina) spinifera (Carter, 1887), C. (Cladochalina) rautenfeldi (Topsent, 1928), C. (Cladochalina) asparagus (Lamarck, 1814), C. (Cladochalina) aspericornis (Lamarck, 1814) and C. (Cladochalina) plancella (Lamarck, 1814) are insufficient and they remain as unique records of the respective species. Callyspongia (Cladochalina) affinis (Hentschel, 1912), compared to our specimens, has spicules different in shape and size (tornotes of 100 µm). Callyspongia (Cladochalina) glomerata (Whitelegge, 1897), C. (Cladochalina) foliacea (Esper, 1797) and C. (Cladochalina) pergamentacea (Ridley, 1881) have a different shape (respectively cake-shaped with tubes, sub-erect and irregular shape and massiveglobular shape).

Other species differ in the characteristics of the skeleton: C. (Cladochalina) diffusa (Ridley, 1884), C. (Cladochalina) oriamensis Pulitzer-Finali, 1982, C. (Cladochalina) spinosissima (Dendy, 1887), C. (Cladochalina) spinilamella (Dendy, 1889) and C. (Cladochalina) thurstoni (Burton, 1930) have different shapes of the meshes, while C. (Cladochalina) subarmigera (Ridley, 1884) has thicker choanosomal fibers and unispicular ectosomal fibers; C. (Cladochalina) saramensis (Wilson, 1925) has smaller choanosomal fibers of 40–50 µm. Callyspongia (Cladochalina) fibrosa (Ridley & Dendy, 1886) differs in the spicule size (100× 3.2 µm) and in the general morphology (branched).

The morphology, the skeleton and the spicule size of the specimens entirely fit the original description of Callyspongia (Cladochalina) aerizusa Desqueyroux-Faundez, 1984 .

The hydroid Zyzzyzus warreni Calder, 1988 (Class Hydrozoa, Phylum Cnidaria) grew on two specimens.

This is the first record of C. (Cladochalina) aerizusa in the Indian Ocean. Hitherto, others were in the Great Barrier Reef and in New Caledonia, where the holotype was recorded.