Endectyon Topsent, 1920

Sitjà, Cèlia & Maldonado, Manuel, 2014, New and rare sponges from the deep shelf of the Alboran Island (Alboran Sea, Western Mediterranean), Zootaxa 3760 (2), pp. 141-179 : 168

Genus Endectyon Topsent, 1920

Diagnosis. Prominently hispid, conulose surface, and typically arborescent growth form. Skeleton with marked axial and extra-axial differentiation; axial skeleton with well-developed spongin fibres forming a compressed reticulation, cored by stout choanosomal styles; extra-axial subectosomal skeleton being radial or plumose, with multi- or paucispicular tracts of long subectosomal styles (subgenus Endectyon ) or choanosomal styles (subgenus Hemectyon ), sometimes connected by unispicular tracts forming hexagonal meshes, usually protruding the surface. Ectosomal skeleton varies from typical raspailiid condition, with thin ectosomal styles grouped in brushes around protruding subectosomal styles (subgenus Endectyon ), to surface brushes composed of subectosomal styles only (nominal genus Basiectyon ), to brushes of acanthostyles surrounding choanosomal styles (subgenus Hemectyon ). Erect brushes of echinating acanthostyles located on the outer margin of the axial skeleton, making a boundary between the extra-axial and axial regions, or forming plumose brushes along the length of the extra-axial tracts, or localized exclusively at the base of the sponge (nominal genus Basiectyon ). Structural megascleres are smooth styles of 2–3 size categories, along with echinating acanthostyles and/or acanthostrongyles with peculiar strongly curved (clavulate) hooks on the shaft, base, and/or apex. Microscleres are absent (sensu Hooper 2002b).