Hymedesmia (Hymedesmia) pansa Bowerbank, 1882

Evcen, Alper, Çinar, Melih Ertan, Zengin, Mustafa, Süer, Serdar & Rüzgar, Melih, 2016, New records of five sponge species (Porifera) for the Black Sea, Zootaxa 4103 (3), pp. 267-275 : 268-269

Hymedesmia (Hymedesmia) pansa Bowerbank, 1882

Figure 2 A, 3A, 4A(1, 2, 3)

Hymedesmia pansa Bowerbank & Norman 1882 , 56; Pulitzer-Finali 1983, 562.

Material examined. ESFM –POR / 2014–001, October 2013, 30 m, on stone in sandy bottom, 1 specimen.

Description. Specimen is cushion-shaped, white (fixed specimen) ( Fig. 2 A). Sponge surface is covered nonerected oval pores. The sponge tissue is soft and fragile. Spongin is scarce. Skeleton has a hymedesmoid arrangement. Ectosomal spicules composed of 2–3 bundles of tornotes comprise a column. Skeleton ( Fig. 3 A) of the ectosome consists of brushes of tornotes. Choanosomal spicules comprise megascleres (tornotes and acanthostyles) and microscleres (isochelae). Tornotes are slender and straight (subtylo) (190–220 x 2–3 µm) ( Fig.

4A1). Acanthostyles (80–220 x 4–8 µm) are obviously spined along the whole length ( Fig. 4 A2). Microscleres are arcuate isochelae (10–20 µm) with flattened shaft ( Fig. 4 A3) and no sigmas.

Habitat and distribution. This species was found on a stone at 30 m in the Black Sea. It is a common on hard substrata (rocks, stones, shells) in the infralittoral and shallow circalittoral zones of the British coasts ( Goodwin et al. 2011) and the Western Mediterranean Sea ( Harmelin et al. 2003, Ackers et al. 1992). This species has not been reported from the eastern Mediterranean and Black Sea.

Figures

FIGURE 2. Photographs of sponges: A. Hymedesmia (Hymedesmia) pansa, B. Chalinula renieroides, C. Haliclona (Halichoclona) fulva, D. Haliclona (Rhizoniera) rosea, E. Ircinia variabilis (scale bar: for A = 20 cm, B = 20 cm, C = 15 cm, D = 10 cm, E = 25 cm).

FIGURE 3. Skeleton networks of sponges: A. Hymedesmia (Hymedesmia) pansa, B. Chalinula renieroides, C. Haliclona (Halichoclona) fulva, D. Haliclona (Rhizoniera) rosea E. Ircinia variabilis: 1. secondary fibres, 2. primary fibrils, 3. thin filaments. (Scale bar: for A = 150 µm, B = 180 µm, C = 150 µm, D = 130 µm, E 1, 2 = 100 µm, E 3 = 120 µm).

FIGURE 4. Spicules of sponges: A. Hymedesmia (Hymedesmia) pansa: 1. straight (subtylo) tornotes, 2. acanthostyles, 3. arcuate isochelae, B. Chalinula renieroides: curved oxeas, C. Haliclona (Halichoclona) fulva: fusiform oxeas, D: Haliclona (Rhizoniera) rosea: oxeas (Scale bar: A 1 = 30 µm, A 2 = 30 µm, A 3 = 10 µm, B = 20 µm, C = 40 µm, D = 25 µm).