A sunfish that does not look like one: instead of the mola's giant gray dinner plate, this is a smooth oval body a meter (3 ft) long, silver-blue and patterned with pale bars, ending abruptly in a fringe where a tail would be. The mouth is a small permanently open vertical slit.
It is the fastest of the family. Where a mola drifts, this one swims properly, sculling with the dorsal and anal fins, and it lives in open water on jellyfish, salps and other soft plankton rather than lying at the surface. The little that is known about its behavior comes from strandings, because it is almost never seen alive by anyone.
That is the standing puzzle: mass strandings of hundreds of them happen periodically on Australian and southern African beaches, always fish of similar size, and nobody knows why. Storms, cold water and disease have all been proposed.
The skeleton is mostly cartilage and the body has no swim bladder, which for a fish that lives in open water means it must swim to stay off the bottom. What washes up looks like a mistake and is in fact a competent oceanic animal that has simply lost its argument with the weather.
The genus. Ranzania Nardo 1840 - -ia (belonging to Camillo Ranzani). ETYFish
The species. Ranzania laevis (Pennant 1776) - smooth. ETYFish
- oval flattened body ending abruptly in a fringe, with no real tail
- silver-blue with a pattern of pale bars and lines over the head and flank
- small round mouth, permanently open and fixed in a vertical slit
- length up to 1 m
Why it's threatened
There are no known major threats for this species.
Threat classification from the IUCN Red List.
