Clathrina brasiliensis Solé-Cava, Klautau, Boury-Esnault, Borojevic & Thorpe, 1991

Klautau, Michelle & Borojevic, Radovan, 2001, Sponges of the genus Clathrina Gray, 1867 from Arraial do Cabo, Brazil, Zoosystema 23 (3), pp. 395-410 : 403-404

Clathrina brasiliensis Solé-Cava, Klautau, Boury-Esnault, Borojevic & Thorpe, 1991

( Fig. 5 ; Table 5)

Clathrina brasiliensis Solé-Cava et al., 1991: 382 , tabs 1; 2.

TYPE MATERIAL. — Holotype, 16.XII.1986, coll. G. Muricy, Muséum national d’Histoire naturelle, Paris ( LBIM.C.1989.2).

TYPE LOCALITY. — Arraial do Cabo (Enseada), Rio de Janeiro, Brazil.

ETYMOLOGY. — For the type locality.

MATERIAL EXAMINED. — Oasis Coralino. Enseada and the Upwelling Area. Gruta Azul, some specimens collected under rocks held together by Palythoa sp. and on the walls of the Gruta Azul.

but sometimes they only appear as large conical triactines. They are strictly localised on the surface of the external tubes, delimiting the cormus. C. brasiliensis has a sciaphile habitat, and can be found under rocks; under the soft coral Palythoa sp. in the Oasis Coralino; and also on the walls of the Gruta Azul.

DESCRIPTION

Specimens of this species are white in life and in alcohol. The cormus is composed of thin, regular and tightly anastomosed tubes. Oscula are simple apertures surrounded by a thin membrane, and localised on the top of conical projections. They receive the water from water-collecting tubes. No special characteristic features were found on the histological slides.

Three types of spicules compose the skeleton: triactines, tetractines ( Fig. 5A ) and tripods ( Fig. 5B ). The triactines and the tetractines are equiradiate and equiangular, with conical actines and blunt ends. They have no special organisation. The apical actine of the tetractines ( Fig. 5B ) is shorter and thinner than the basal ones, and it is conical, sharp and covered with short spines. The apical actine is always projected into the tubes. Tripods are less equiangular, sometimes they are even sagittal. They have frequently their centre arisen, REMARKS

Specimens of C. brasiliensis are morphologically very similar to the specimens of C. cerebrum from the Adriatic and the Mediterranean Sea. They were recognised as distinct species only after genetic studies (Solé-Cava et al. 1991), which have shown that there was no gene flow between these two populations. They are morphologically very similar indeed. The only differences we could find to date are the size of the spicules (Table 5), a little longer and thinner in the Mediterranean specimens (triactines: 85 [± 7] / 7 [± 1] µm; tetractines: 83 [± 9] / 7 [± 1] µm; tripods: 89 [± 15] / 11 [± 2] µm); and the size of the spines of the apical actine, which is also larger in C. cerebrum .

Figures

FIG. 5. — Clathrina brasiliensis Solé-Cava et al., 1971, holotype (LBIM.C.1989.2); A, spicules; B, tripod, as a large triactine and the spined apical actine of a tetractine. Abbreviations: tr, triactines; te, tetractines. Scale bars: A, 100 µm; B, 50 µm.