Flagtail
The flagtails (' or ' in the Hawaiian language) are a family (Kuhliidae) of perciform fish of the Indo-Pacific area. The family consists of several species in one genus, Kuhlia. Most are euryhaline and often found in brackish water, but the genus also includes species restricted to marine or fresh water. Several species are known as Hawaiian flagtails, particularly "K. sandvicensis" and "K. xenura". Etymology. The genus "Kuhlia" is named for the German zoologist Heinrich Kuhl (1797–1821). Description. The distinctive characteristic of these fish is a scaly sheath around the dorsal and anal fins. The dorsal fin is deeply notched  between the 10 spines and the 9 to 13 soft rays. The opercle has two spines, and the anal fin three. Their bodies are compressed and silvery, and they tend to be small, growing to 50 cm at most. During the day, they usually school, dispersing at night to feed on free-swimming fish and crustaceans. Species. The currently recognized species in this genus are: