A silver disc of a fish standing on edge in open water, deep-bodied and blunt-headed as an adult, and something else entirely when young. Juveniles trail fin filaments several times their own length and drift with them extended, which reads as a jellyfish rather than a fish and buys a small animal a great deal of time.
It shares that trick with the African Pompano, and the two are constantly confused. The tell is the head: this species keeps a steeper, more angular forehead, and its bars persist longer into adolescence. Both lose the threads as they grow, which is why the adults look like different fish from the juveniles.
Adults hunt in midwater along reef edges, taking small fish and crustaceans, and they are strong enough swimmers to work current-swept corners where little else holds position.
Juveniles come inshore over shallow sand, and that is where a diver is most likely to meet one: a lone silver shape with impossible trailing fins, hanging near the bottom in a lagoon and looking nothing like the fish it will become.
The name is worth a note, because it has been attached to two different fish. Ruppell described this one from the 🌊 Red Sea in 1830. Cuvier later used the same combination for what turned out to be the African Pompano, and that second name is the one taxonomists discarded. Databases now move Ruppell's fish into the genus Scyris, so it appears as Scyris indica in some places and as Alectis indica in most others, including the regional guide.
- very deep, laterally flattened silver body with a steep forehead
- juveniles trailing long thread-like fin filaments
- faint dark bars on the upper body, fading with age
- adults large and blunt-headed, in open water
