Pennant Butterflyfish

Heniochus diphreutes

Brightly colored butterflyfish are a typical coral reef fish, and they are often seen dashing along the ocean's gardens. They have disk shaped bodies, which is advantageous when navigating through narrow spaces. They can quickly move out of reach for predators, and most species have a dark bar through the eye, which successfully disguises it. Some species of butterflyfish have a false eyespot near their tail. The travel in pairs and mate for life. Despite these long term partners, these fish do not offer parental care for their young. They release their eggs into the water, and after hatching the larvae drifts with plankton for weeks or months. Butterflyfish are distinguished by small, bushlike teeth. The family name, Chaetodontidae, is a combination of chaeto ("hair") and dentis ("tooth"). 24 species of butterflyfish are found in the Hawaiian Islands. In ancient Hawai'i, one general name for butterflyfish is kīkākapu meaning "strongly prohitited," and are described in several oli or chants as sacred. Other names are lau-hau, which means "leaf of the hau tree," or lau-wiliwili meaning "leaf of the wiliwili tree."

The Pennant Butterflyfish are boldly patterned with white and black vertical bars, and their soft dorsal and tail fins are yellow. They have distinct bright white pennants, which increase in length as they grow. Rare specimens have a double pennant! Pennant butterflyfish like to school along dropoffs, usually at depths of 40 feet or more. They will occasionally swim through shallow water. They grow to about 8 inches.