It is not an eel. It is a dottyback that gave up on being fish-shaped.
This animal sits in the same family as the magenta and gold two-inch cave fish on the rest of these cards, and it is a fifteen-centimeter ribbon that pushes through seagrass and rubble like a snake. The dorsal and anal fins have merged with the tail into one continuous fin running around the back end, the body is round in section, and the pelvic fins are nearly gone.
Everything about that is what happens when a fish takes up living in tight spaces full time. The same body has been arrived at independently by true eels, snake blennies, worm gobies, pearlfish and several others, from completely different starting points, because there is really only one shape that works for pushing between roots and under rubble: long, smooth, and with nothing sticking out to catch.
So the family that produced the reef's most aggressive small territory holder also produced this. Look for it in shallow seagrass rather than on coral, dark with pale spots, moving in a way no dottyback should move.
The genus. Haliophis Rüppell 1829 - halos (sea) + ophis (snake). ETYFish
The species. Haliophis guttatus (Forsskål 1775) - spotted. ETYFish
- eel-like body, three times longer relative to its depth than any dottyback
- dorsal and anal fins running into the tail as one continuous fin
- dark with pale spots along the flank
- shallow, in seagrass and rubble rather than on coral
- up to 15 cm
Why it's threatened
There are lots of small-scale artisinal fisheries that overlap with parts of its range, though it is unknown if these activities threaten this species directly.
Threat classification from the IUCN Red List.
