A small, deep-bodied fish whose flesh is clear enough to show its own spine through the side, so that a shoal reads as a shimmer with a scatter of silver gut sacs and eyes hanging in it. Transparency is the whole defence: in open water with nothing to hide behind, the fish that cannot be resolved is the fish that is not eaten.
Shoals hang in the shade through the day - under a jetty, inside a wreck, in the roof of a shallow cave - packed tight and barely moving, then spread out at dusk to pick zooplankton out of the water. The species tolerates brackish water better than most reef fishes, so mangrove creeks and lagoon edges hold it in numbers, and it can turn up where the salinity swings with the tide.
The family is better known from aquarium shops than from the sea, and not to its credit. The garish "painted" glassfish sold there is an ordinary transparent fish injected with dye, a practice that kills most of the fish it is done to and fades on the survivors. Nothing in this animal is coloured; it is worth seeing precisely because it is not.
- body transparent enough to show the spine through the side
- silvery gut sac and large eye standing out in an otherwise clear fish
- small and deep-bodied, in slow dense shoals in the shade
- length up to 12 cm
