Waipio Valley Stream Restoration Study

Insects: Native Species

Scientific name: Geranomyia advena
Common name(s): Hawaiian-Beaked Crane Fly

Geranomyia advena

Status: Endemic

Habitat: Surfaces of wet rocks, but also brackish water canals

Preferred Area of Stream: Riffles and wet rocks in streams, often found at the water’s edge on stream rocks, and in moss under waterfalls.

Range in Hawai‘i: All main Hawaiian Islands

Diet: Seems to be fairly omnivorous and will eat decaying plant material, probably algae, and other aquatic insects

Predators: Spiders, dragonflies and damselflies, wasps, Saldid bugs, Microvelia vagans, long-legged aquatic flies, native and introduced fish

Fact: The Hawaiian-beaked crane fly is readily distinguished from all other Hawaiian craneflies because its elongated mouthparts make it resemble a mosquito, however, the much longer legs will indicate that it is in fact a crane fly and will not bite. They are one of the most versatile aquatic insects and can be found from sea level to the Alaka‘i swamp area of Kauai at over 4000 ft (1220 m).