Dendoricella flabelliformis (Hansen, 1885) is a brownish, broadly erect, leaf-shaped sponge. Rather soft in consistency with uneven surface. It spiculation of oxeas and arcuate isochelae is unique (microscopic examinaton). It is a northern deep water species.
Colour: Light brownish grey in alcohol.
Shape, size, surface and consistency: Erect, broad, leaf-shaped sponge. Size up to 9 cm high and wide. Surface rather rough. Oscules on the rim. Consistency rather soft.
Spicules: (Dendoricella flabelliformis sp) Megascleres: Oxeas only, in two size categories: choanosomal oxeas 410-550 µm, ectosomal oxeas 268-350 µm.
Microscleres: Arcuate isochelas, robust, strongly curved, with alae often almost touching, sometimes slightly asymmetric: 30-40 µm.
Skeleton: Ectosomal: brushes of oxeas, scattered single oxeas. Choanosomal: plumose bundles of oxeas, sparingly connected by single oxeas; spongin visible only in the stalk.
Ecology: Deep water, 90-1097 m.
Distribution: Norway; Arctic.
Etymology: The name refers to the shape of the species.
Type specimen information: No data.
This species is usually assigned to Isodictya, because of the spiculation of oxeas and chelae. However, the type of Isodictya, I. palmata, has palmate isochelae and the skeleton is strictly anisotropic, whereas flabelliformis has arcuate isochelae and the skeleton is more plumose.
Source: Arndt, 1935.