Sargassum cf. acinarium (Linnaeus) Setchell

Fig. 19A, B

Fucus acinarius Linnaeus. Basionym.

Fucus acinarius S. G. Gmelin, Fucus linariifolius Turner, Fucus linifolius Turner, Sargassum linifolium C. Agardh, Sargassum linifolium f. gibraltica Grunow, Sargassum vulgare var. linifolium (C. Agardh) Zanardini. Synonyms.

Morphology of specimens from Pantelleria.

Sargassum cf. acinarium is attached to the substrate by small discoid holdfast. Primary branches are cylindrical and knotty. Foliaceous branches are narrow (ca. 0.5-1 cm) with an evident midrib, acute apex and denticulate or entire margin. This species has spherical aerocysts with a cylindrical pedicel. During the monitoring, some specimens showed receptacles.

Habitat.

S. cf. acinarium was observed during scuba dives at Punta Spadillo, Cala Tramontana and Cala Levante, in the lower infralittoral/circalittoral (from 28 to 45 m).

Distribution.

This seaweed is distributed in the north-western Atlantic (from Spain to Guinea-Bissau) and in the Mediterranen Sea ( Blanfuné et al. 2022).

Remarks.

The identification at species level was not certain because it was not possible to collect the receptacles of this entity.