Carter, 1875
Definition: Encrusting, massive, cup- and plate-shaped growth forms, with ostia on one (out-)side and oscules on the other (in-)side; megascleres calthrops, short-shafted triaenes, and oxeas; microscleres streptasters of various types (metasters, plesiasters, spirasters and amphiasters), but never euasters. desmas are common in some genera ('lithistid' or 'sublithistid'). Review: Maldonado (1993).
Source: Hooper's Internet Sponge Guide.
Genera represented in the area:
Dercitus Gray, 1867 (type species: Hymeniacidon bucklandi Bowerbank, 1866) (syn. Calcabrina Sollas, 1888; Stoeba Sollas, 1888): dichotriaenes and spined microrhabds (sanidasters) and sometimes toxa-like microrhabds.
Pachastrella Schmidt, 1868 (type species: Pachastrella monilifera Schmidt, 1868) (syn. Nethea Sollas, 1888): irregular cups or massive; megascleres short-shafted, almost isoactine triaenes in different sizes; microscleres streptasters and microrhabds.
Poecillastra Sollas, 1888 (type species: Normania crassa Bowerbank in Norman, 1869) (syn. Normania sensu Bowerbank, 1869; Characella Sollas, 1888): plate-like growth form with differentiated oscular and poral surface; megascleres oxeas and short-shafted orthotriaenes / orthodichotriaenes; microscleres streptasters and microxeas.
Remark: The synonymy with Characella is contested by Boury-Esnault et al. (1994) based on subtle differences in the distribution of the triaenes: Characella would have the triaenes exclusively in the ectosomal region, while Poecillastra would have them distributed throughout the skeleton.
Vulcanella Sollas, 1888 (type species: Sphinctrella ornata Sollas, 1888) (syn.: Sphinctrella Schmidt, 1870 (preoccupied); Sphincterella De Laubenfels, 1936): encrusting or massive with pores generally dispersed and only a few highly specialized oscules opening into a large cloaca; megascleres calthropses of different sizes and oxeas; microscleres streptasters and rugose microxeas.
Species included:
Dercitus bucklandi
Pachastrella monilifera
Poecillastra compressa
Species not treated here:
Pachastrella intexta Carter (1876), deep water
Pachastrella ovisternata Lendenfeld (1897), Portugal, deep water
Poecillastra sollasi Topsent (1904), North Atlantic, deep water
Poecillastra amygdaloides (Carter, 1876), deep water
Poecillastra armata Hanitsch (1895), W coast of Portugal, insufficient information.
Poecillastra pachastrelloides (Carter, 1874), Straits of Gibraltar, Ireland, deep water
Vulcanella annulata (Schmidt, 1870), Norway, deep water
Vulcanella horrida Schmidt, 1870, North Atlantic, deep water
Vulcanella ornata (Sollas, 1888), Ireland, deep water