The lips do the work, and they are the first thing anyone notices: thick, rubbery, and pushed forward, on a fish that otherwise looks like an ordinary large wrasse.
They are a seal. This wrasse feeds by taking a mouthful of sand and rubble, closing those lips around it, and processing the load inside the mouth - sorting the animals out, spitting the sediment through the gills, and swallowing the rest. Doing that with thin lips would mean losing half the mouthful on the way in. Fleshy ones let it take a proper bite of the bottom and keep it.
So it works ground that other reef fish give up on: coarse sand, broken rubble, the mixed stuff at the base of the reef where things are buried rather than sitting in the open.
The two halves of an adult do not match. The front is pale gray-green and the rear is abruptly much darker, as though the fish was dipped, and juveniles carry a completely different arrangement with a white rear body and a yellow tail.
The genus. Hemigymnus Günther 1861 - hemi- (partial) + gymnos (bare or naked). ETYFish
The species. Hemigymnus melapterus (Bloch 1791) - mela- (black) + pterus (fin). ETYFish
- very thick fleshy lips, obvious at any distance
- adults with a pale front half and an abruptly dark rear half
- juveniles with a white rear body and a yellow tail
- up to 40 cm
Why it's threatened
There are no major threats known for this species, although it is targeted by spearfishers and is collected for the aquarium trade and in multispecies fisheries.
Threat classification from the IUCN Red List.
