What is "centriscidae"

The Centriscidae are a family of fishes from the order Syngnathiformes which includes the snipefishes, shrimpfishes, and bellowfishes. A small family, consisting of only about a dozen marine species, they are of an unusual appearance, as reflected by their common names. The members of the genera Aeoliscus and Centriscus are restricted to relatively shallow, tropical parts of the Indo-Pacific, while the remaining species mainly are found in deeper parts of tropical, subtropical or southern oceans.

Their bodies are highly compressed, and mostly covered with bony plates. The first spine of the dorsal fin is long and sharp, and displaced to the rear of the body; two additional spines, the rest of the dorsal fin, and the caudal fin have all moved to the ventral side of the fish. Their snouts are also long and narrow, and the small mouths at the end have no teeth. All species are small, no more than .

As if their shapes were not strange enough, centriscids also swim head down. The reason for this is unclear; while some species blend in with sea grass, others live on coral reefs, where there is no apparent advantage to vertical positioning. They feed on zooplankton.