A glass-clear goby two centimetres long, sitting still on a sponge or a leather coral.
A tiny goby, rarely more than 2.5 cm, with a glass-clear body through which the vertebral column shows as a pink to orange line and the gut as a small silver mass. There is a red-brown patch over the eye and usually a reddish smudge at the base of the tail. The pelvic fins are fused into a disc that holds the fish against whatever it is sitting on. The genus contains a number of similar species separated chiefly by host and by fine detail of the head and snout pigment: Pleurosicya mossambica is the generalist of the group, recorded from leathery soft corals, sponges, sea squirts, algae, seagrass blades and the mantle of giant clams, while several congeners are tied to a single host such as a Dendronephthya colony or a mushroom coral. Photographs are often not resolvable below genus, and host alone is not conclusive.
Sits motionless on the surface of its host and feeds on small planktonic crustaceans taken from the water immediately above it, returning to the same spot each time. Its response to a diver is not to flee but to shuffle round the host to the far side, which is what usually ends an attempt at a photograph. Recorded from about 3 to 30 m. Because the body is transparent, the animal is found by picking out the pair of dark eyes and the orange spinal line against the host rather than by looking for the outline of a fish, and a sponge or leather coral that appears to have two small eyes on it generally has a ghost goby on it.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.
