Dictyonella pelligera (Schmidt, 1864) is a yellow-orange massive-lobate soft sponge with strongly conulose surface. It is a Mediterranean species recorded once in the Roscoff area, NW France.
Colour: Ochre-beige or orange-pink.
Shape, size, surface and consistency: Massively lobate to lowly ramose with relatively thin, erect, irregular lobes/branches. Size up to 4 cm high, lobes/branches up to 1 cm in diameter. Surface strongly conulose caused by projecting spicule tracts. Oscules not apparent. Consistency soft, compressible.
Spicules: (Dictyonella pelligera spics) Styles, often with telescoped ends, curved: 440-700 x 3-10 µm.
Skeleton: Dendritic spongin-encased spicule tracts fan out towards the surface, where they end in the surface conules.
Reproduction: August to September (Mediterranean).
Ecology: On stones at 75 m (Roscoff), on rock faces at 25-35 m, in caves in more shallow depths (Mediterranean).
Distribution: Roscoff; Mediterranean.
Etymology: pelliger = having a skin, referring to the organic skin stretched over the endings of the choanosomal spicule tracts.
Type specimen information: The type specimens are in the Graz Museum, LMJG 15514 and 15517. Type slide under Clathria in London: BMNH: 18184.108.40.206.
Several closely similar species occur in the Mediterranean (D. incisa Schmidt, 1868, D. marsilii Topsent, 1938, D. alonsoi Carballo et al., 1996), discriminated mostly on the basis of spicule sizes. In the study area, the only closely related species is D. madeirensis (Topsent, 1928) recorded likewise once from Roscoff. It differs from D. pelligera in the more anastomosed skeletal tracts and the much thicker styles (up to 30 µm).
D. pelligera shares a feature with the Mediterranean Scopalina lophyropoda, viz. the granulated surface membrane, and it is not entirely impossible that pelligera fits better in Scopalina. This matter is left for a future revision of Mediterranean-Atlantic Dictyonellidae.
Source: Topsent, 1925a.