Genus: Free-living; skeleton with or without coat; spicules included in a coat more or less visible; radial siliceous spicules; ordered spicules (Illustrated Guide, 1985). Mucilaginous envelope with spindle-shaped or discoidal spicules which extend normally outwards along pseudopodia (Kudo, 1966). Species:

50 μm 100 μm 150 μm; x 400 : 31 μm 63 μm 94 μm; x 640