Clathria (Clathria) intermedia (Burton, 1930a) forms a massive crust with smooth surface. It is known only from a single record from Norwegian waters. It is readily distinguished from the many other Clathria species by its lack of toxas (microscopic examination necessary).
Colour: Greyish yellow in the dry state.
Shape, size, surface and consistency: Sponge irregularly massive and low-growing. Surface smooth, even. Pores and oscules not apparent. Texture soft, compressible, friable.
Spicules: Megascleres: Subtylostyles with faintly spined heads: 510 x 8 µm; acanthostyles, slightly curved, entirely covered with minute inconspicuous spines: 330 x 9 µm.
Microscleres: Palmate isochelae: 24 µm.
Skeleton: Ectosomal: a loose tangential reticulation of acanthostyles and subtylostyles. Choanosomal: a loose irregular reticulation of acanthostyles and subtylostyles.
Ecology: No data.
Distribution: Norway, no further data.
Etymology: The name refers to the opinion of Burton that this material was intermediate between Mycale and Clathria.
Type specimen information: The type is in the Natural History Museum, London, BMNH 1910:1:1:1912 (slide). Norman Collection.
There is only a single record of a dried specimen of this species. Its status and generic assignment is uncertain.
Source: Burton, 1930a.