Ridley and Dendy, 1886
Definition: Encrusting, massive, cup-shaped, fan-shaped and branching sponges. Megascleres are usually styles, sometimes also including oxeas or strongyles. Spicules are typically enclosed within plumose, reticulate, halichondroid-reticulate or compressed axial fibres. Microscleres are diverse, always consisting of sigmas, and often including microxeas of several sizes, raphides in bundles or individually, and commas. Chelae are absent.
Remarks: 17 nominal genera are included in the revised Desmacellidae, of which only 8 are thought to be valid. Review in Hooper et al. (1991). Only three genera appear to occur in the area.
Source: Hooper's Internet Sponge Guide.
Genera represented in the area:
Biemna Gray, 1867 (type species Desmacidon peachi Bowerbank, 1866) (syn. Allantophora Whitelegge, 1907; Toxemna Hallmann, 1917): plumose or plumo-reticulate choanosomal skeleton, with variable development of spongin fibres cored by styles or subtylostyles of a single size, an erect ectosomal skeleton and often shaggy surface, and microscleres include sigmas and raphides, and sometimes microxeas, commas, microstrongyles and spheres.
Desmacella Schmidt, 1870 (type species D . pumilio Schmidt, 1870) (syn. Sigmatoxella
de Laubenfels, 1936; Sigmotylotella Burton, 1932; Tylodesma Thiele, 1903; Tylosigma Topsent, 1904) reticulate, plumo-reticulate and vaguely halichondroid choanosomal skeleton, poorly developed spongin fibres, a tangential halichondroid ectosomal skeleton all cored by tylostyles of one or more sizes, microscleres sigmas and raphides.
Dragmatella Hallmann, 1916 (type species: Desmacella aberrans Topsent, 1892a): massive growth form; surface with digitiform tapering processes; choanosome is cavernous, without axial condensation, consisting of well-developed, non-plumose, multispicular spongin fibres cored by styles, arranged in more-or-less dendritic structure, diverging and ascending to the surface; ectosome with choanosomal styles lying tangential to the surface, criss-crossing in every direction; microscleres are raphides with occur singly or in bundles (trichodragmata).
Species included:
Biemna variantia
Desmacella annexa
Desmacella inornata
Species not treated here:
Desmacella informis Stephens (1916), Ireland, deep water
Desmacella rosea (Fristedt, 1887), Iceland, deep water
Dragmatella aberrans Topsent (1892), North Atlantic, deep water.