Caption

Fairy shrimp. Coloured scanning electron micrograph (SEM) of a female fairy shrimp (order Anostraca). Fairy shrimps swim around on their backs, propelled by their constantly moving legs. Fairy Shrimps lack a carapace, and are considered to be rather primitive as they have a relatively large number of segments and the legs are not specialised. The body is elongated, and bears 11 pairs of legs fringed with bristles; the head curves downwards, and in males the second pair of antennae are modified 'claspers' for grabbing females during mating. They grow up to 25mm in length. They inhabit temporary pools, ranging from ponds to muddy ruts. Fossils of fairy shrimps have been found in Cambrian rocks in Sweden. Magnification: x 15 at 10 centimetres high.