Bluespotted cornetfish

Once you have seen one you cannot mistake it. The body is a long, thin, flattened tube, olive to silvery brown above and pale below, with a long bony snout ending in a small mouth, and a tail that carries a fine trailing filament longer than a diver's finger. Rows or pairs of small pale blue spots run along the back, sometimes joining into faint dashed lines, and the fish can switch its pattern from plain silver to dark banded in seconds. Maltese fish are usually 60 cm to a metre; the maximum is about 1.6 m, mostly tail.

It hovers rather than swims, hanging almost motionless over sand, Posidonia and reef edges, often angled slightly nose-down, and it approaches prey with extraordinary slowness before sucking in a small fish through that pipe of a snout. Divers around Malta and Gozo meet it from a few metres down to about forty, most often over the seagrass and sand margins and along the shallow reef at sites like Cirkewwa, Comino, Dwejra and Xlendi.

It is not a Mediterranean native. Fistularia commersonii came from the Red Sea through the Suez Canal, reached the eastern Mediterranean at the turn of the millennium and crossed the basin faster than any other Lessepsian fish, with the first Maltese record from Xwejni Bay in Gozo in 2005 and regular sightings since. It is now a permanent part of the Maltese fish community, and sightings are still worth reporting to the Spot the Alien Fish campaign.