Hyrtios collectrix (Schulze 1880)

Growth form sub-spherical or cake shaped, usually less than 10 cm in diameter. Colour black at the surface, greyish-yellow in the choanosome. Consistency very spongy in vivo, quite brittle in dry conditions. Surface conulose (conules 1–2 mm high, 1–2 mm apart). Oscules small, scattered and inconspicuous. Ectosome leathery, densely packed with highly heterogeneous detritus in nature, shape and size. Choanosome moderately cavernous and fleshy, with a ground-work of fibro-reticulations. Flagellate chambers rounded, 25–40 µm in diameter. Skeleton composed by very rare fibres completely filled by foreign materials, ascending primaries (100–350 µm in diameter), secondaries 50–100 µm, meshes very irregular in size, shape and outline; a large amount of variously composed and sized detritus is scattered in disorder in the mesohyl.