''Clathrina clathrus'' is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

calcareous sponge The calcareous sponges or calcereans are sponges that make up the class Calcarea, characterized by spicules made of calcium carbonate in the form of high-magnesium calcite or aragonite. While the spicules in most species are triradiate (with three ...

belonging to the family

Clathrinidae Clathrinidae is a family of calcareous sponges in the order Clathrinida. It contains the following genera: *''Arturia'' *'' Ascilla'' *'' Borojevia'' *'' Brattegardia'' *''Clathrina ''Clathrina'' is a genus of calcareous sponge in the family ...

. This yellow (occasionally white) sponge, up to 10 cm in diameter, usually appears cushion-shaped at a distance (its close relative ''

Clathrina coriacea ''Clathrina coriacea'' is a species of calcareous sponge belonging to the class Calcarea and family Clathrinidae. Species in the genus Clathrina are composed of calcium carbonate tube-like skeletons containing spicules. The sponge can be locate ...

'' is normally flatter in appearance). Close-up the sponge can be seen to consist of a tangled mass of tubes (these tubes are thicker and less tightly knit than in ''C. coriacea'' and there is no

osculum The osculum (: oscula) is an excretory structure in the living sponge, a large opening to the outside through which the current of water exits after passing through the spongocoel. Wastes diffuse into the water and the water is pumped through ...

as found in that species). Like ''C. coriacea'', the

spicules Spicules are any of various small needle-like anatomical structures occurring in organisms Spicule may also refer to: *Spicule (sponge), small skeletal elements of sea sponges *Spicule (nematode), reproductive structures found in male nematodes ( ...

are exclusively three-pointed ''triactines''. This is a shallow-water species found in the Mediterranean and on Atlantic coasts of Europe as far north as the

British Isles The British Isles are an archipelago in the Atlantic Ocean, North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner Hebrides, Inner and Outer Hebr ...

References

''Clathrina clathrus'' at Marine Species Identification Portal

External links

clathrus ''Clathrus'' is a genus of fungi of the family Phallaceae, the stinkhorn fungi. Mature fruit bodies are covered with olive-brown slimy gleba, containing spores, that attract flies. These fungi are saprobic (feeding on dead organic matter) and are ...

Sponges described in 1864 Fauna of the British Isles Taxa named by Eduard Oscar Schmidt {{calcarea-stub