Desmacidon fruticosum (Montagu, 1818)


Family : Desmacididae

Form: Massive-lobose; substantial growths often with massive tubular processes. The processes are simple or coalescent, often fusing at the bases and so resembling malformed, hand-like structures. Sometimes the thicker branches have a longitudinal groove in one side which in life is really an exhalent canal leading to the oscule at the top.

Colour: Yellow to orange, with purple in some specimens.

Smell: None. Slime : Exudes large amounts of slime when removed from the water.

Consistency: "Firm, compressible."

Surface: Bristly.

Apertures: Oscules are at the top of the tubular processes.

Contraction: Not noticeable.

Internal characters

Skeleton: An irregular reticulation of thick multi-spicular fibres of tornotes. There is no special ectosomal skeleton nor any echinating spicules.

Spicules: The megascleres are tornotes (a), with oxeote or mucronate ends, "184-236Ám". The microscleres are spatuliferous anchorate chelae (b) of two sizes, "32-49Ám", and sigmata (c) (of two sizes also?), "29-63Ám".

Habitat: ? Usually on horizontal surfaces. "On mud, sand, gravel, rock, or broken shell." Recent records are from 30m or greater depths.

Distribution: "British Isles; France; Spain." Recent diving records from the Scilly Isles and Galway Bay.

Distribution Map: NBN map : National Biodiversity Network mapping facility, data for UK.

Identity: More information is needed about this species. Anyone finding it is asked to record all possible information and to send it to the editors. The skeletal net of tornote bundles with isochelae and sigmata in a massive yellow sponge which exudes slime is unlikely to be confused with other UK sponges.

Voucher: MNHN Paris.

Editors: J.D. Guiterman, D. Moss, B.E. Picton.

 Picton, B.E., Morrow, C.C. & van Soest, R.W.B., 2011. [In] Sponges of Britain and Ireland