Conica are a cnidarian suborder of the Leptomedusae (thecate hydroids). They make up the bulk of their order; their internal relationships are not well resolved, and most of the roughly 30 families are not yet assigned to a superfamily.
They are named for the distinctive shape of their hypostome, the "tip" of the polyps' body where the mouth is located. As opposed to the smaller thecate suborder Proboscidoidea with their elongated hypostome, the Conica have a simple hypostome without a pregastric cavity and a shape that is generally round or conical.
Well-known members of the Conica are the "air fern" (Sertilaria argentea) of the Sertulariidae which is sold dried as novelty "plants" and aquarium ornaments, and the Crystal Jelly (Aequorea victoria) of the Aequoreidae, a bioluminescent hydrozoan.