The males have two distinctive black spots, one larger spot behind the pectoral fins and one smaller spot at the base of the tail fin. Females only have one spot at the base of tail – so the name can be misleading!

This is a small, thin fish, usually a reddish-brown with paler underside. They are distinct from other gobies in that their eyes are on the side of the head rather than on top.

Behaviour

They are often seen in groups hunting for floating food such as plankton.

Size

Up to 6 cm length.

Status

Common.

Distribution

Common around Scotland, but most prevalent on the west coast of Scotland, and islands.

When to see

March – October.

Facts

When breeding, males develop beautiful iridescent blue lines on their fins!