Ancorina cerebrum Schmidt (1862) is a blue or reddish, globular, hispid, hard sponge with characteristically folded surface, resembling the folds of a human brain. It is a Mediterranean species which penetrates the southern parts of Western Europe.
Colour: Blue, reddish or dirty brown.
Shape, size, surface and consistency: Large, globular to shallow-cup shaped, with a folded surfae like that of a human brain. Size up to 12 cm in diameter. Larger specimens have a central depression or vent of up to 3 cm in diameter and 5 cm deep, which in life may have a membrane covering it. Also there are frequent irregular projections of several mm in diameter issuing from the surface. Surface strongly hispid due to a pelt of projecting spicules. Consistency hard.
Spicules: Megascleres (Ancorina cerebrum megas): oxeas, with stylote or strongylote deviations: 3000-3200 x 50-60 µm; dichotriaenes with a rhabdome of 1600-3200 x 39-60 µm, protocladi of 65 µm and deuterocladi of 75 µm, 30-50 µm in diameter; anatriaenes with a rhabdome of 2600-4100 x 10-33 µm, a cladome of 100 µm in diameter, and cladi of 60-150 µm. Microscleres (Ancorina cerebrum micros): sanidasters, with blunt spines: 5-8 x 2-4 µm; euasters in two categories: large oxyasters 30-35 µm in diameter, and strongylasters in a large, 2-4 rayed form of 20-40 µm, and a small, 5-8 rayed form of 10-15 µm.
Skeleton: Radiate, with distinct cortex (Ancorina cerebrum cross) of 1.5-3 mm in thickness, which is holed by numerous cortical cavities; the cortical megascleres consist mostly of triaenes, which carry the surface microsclere layer and overly a pulpy choanosome consisting mostly of oxeas and oxyasters.
Ecology: No data.
Distribution: Mediterranean and adjacent Atlantic.
Etymology: The name refers to the brain-like convoluted surface.
Type specimen information: Syntypes Graz Museum, LMJG. 15346-47, 15503-04 (Desqueyroux-Faúndez and Stone, 1992)
The species differs fromthe sympatric Ancorina radix in habit characters as well as in the possession of dichotriaenes.
Source: Lendenfeld, 1894.