Marine Biodiversity » Marine Sponges » Calcarea » Calcarea Classification » Subclass Calcinea

Definition: Essentially tubular organisation, with continuous choanoderm lining all internal cavities; growth is by longitudinal median divisions and anastomosis of tubes to form large units called the cormus; neither a common cortex nor a well-defined inhalant and exhalant aquiferous system.

Scope: Two genera (of five named genera) are included in the family.

Reviews: Bidder (1898), Minchin (1909), Dendy (1913), Hartman (1958), Borojevic (1968), Borojevic, Boury-Esnault & Vacelet (1990).

Genera:
Clathrina Gray, 1867 (type species: Grantia clathrus Schmidt, 1864) (syn. Ascetta Haeckel, 1872; Ascaltis Haeckel, 1872; Leucopsis Lendenfeld, 1885) - cormus is composed of anastomosing, irregular reticulation of tubes, usually encrusting, sessile, low growing; smooth surface; oscules not apparent; soft texture; choanoderm is flat or rarely raised up into conuli by the apical rays of the quadriradiates, but never forming true folds, at least when the sponge is in the extended state; spicules are regular equiangular and equiradiate triradiate and/or quadriradiates alone, but sometimes also with biradiates or tripod spicules (Burton, 1963; Borojevic et al., 1990). GBR species: Clathrina heronensis, C. wistariensis, C. adusta, C. parva, C. helveola, C. luteoculcitella Wörheide & Hooper 1999.
Guancha Miklucho-Maclay, 1868 (type species: Guancha blanca Miklucho-Maclay, 1868) - cormus composed of a peduncle and a clathroid body, often composed of small budded colonies of tubular individuals attached to stipitate base; peduncle may be formed by true tubes with a normal choanoderm, or may be solid with a special skeleton; skeleton composed of regular equiangular and equiradiate spicules, to which parasagittal triradiate spicules may be present at least in the peduncle; in some species only parasagittal spicules are present and their unpaired ray is basipetally oriented (Burton, 1963; Borojevic et al., 1990).