Slime mould and beetle. Coloured scanning electron micrograph (SEM) of a slime mould (Physarum polycephalum) flowing over a dead beetle. It is moving to the left; at right is a piece of almond that it has finished feeding on. Slime moulds were once thought to be fungi, but are now classified as a separate group. They have complex life-cycles. The yellow Physarum body is a plasmodium: a mass of protoplasm containing many nuclei. It is effectively a single giant cell, up to 30 centimetres across. Physarum reproduces through spores that germinate into free-living single-celled forms. These eventually fuse to form new plasmodia. Magnification: x9 at 6x7cm size.