Sea Mice

Aphrodita is a genus of marine polychaete worms found in the Mediterranean sea and the eastern and western Atlantic Ocean.^[2]

Several members of this genus are known as "sea mice".

Etymology

Dorsal view, removed from water

The name of the genus is taken from Aphrodite, the Ancient Greek goddess of love, said to be because of a supposed resemblance to human female genitalia.^[3] The English name may derive from the resemblance to a bedraggled house mouse when washed up on shore.^[4]

Description

The body of the sea mouse is covered in a dense mat of parapodia and setae (hairlike structures).^[2] Adults generally fall within a size range of 7.5 to 15 centimetres (3.0 to 5.9 in), but some grow to 30 centimetres (12 in). The sea mouse has two pairs of feeler-like appendages close to the mouth and does not have eyes. Locomotion is carried out by several small, bristly, paddle-like appendages. They are hermaphroditic which means that they have functional reproductive organs of both sexes. The eggs of one individual are fertilised by the sperm of another.^[5]

Structural coloration

The spines, or setae^[2] on the scaled back of the sea mouse are a unique feature. Normally, these have a deep red sheen, warning off predators, but when the light shines on them perpendicularly, they flush green and blue, a "remarkable example of photonic engineering by a living organism". This structural coloration is a defense mechanism, giving a warning signal to potential predators. The effect is produced by many hexagonal cylinders within the spines, which "perform much more efficiently than man-made optical fibres".^[6]

Feeding

Aphrodita are typically scavengers.^[2] However, Aphrodita aculeata is an active predator,^[7] feeding primarily on small crabs, hermit crabs and other polychaete worms such as Pectinaria.^[7]

Species

Species recognized by the World Register of Marine Species:^[1]

References