Tree Cone Cosmet Moth (Hyposmocoma opuulaau)
This species from the island of Maui was described in the year 2011.
The larval case of this species is a small and thin, elongate cone-shaped, up to 0,9 cm long structure, and is decorated with very small bits of sand and dried plant pieces which are woven with silk filaments on the dorsal half of the case. The case is bicolored, being pale gray to silvery on the ventral side. It furthermore has an operculum which can be closed by the larva from the inside.
The larvae were found on and beneath the bark of Swamp Mahagony trees (Eucalyptus robusta Sm.), a tree species that is not native to the Hawaiian Islands, and that was only introduced by men. They most probably feed on algae and lichens, crowing on the bark.
The adult moths have very dark grey to nearly black colored forewings, the hindwings are a shade lighter.
They have a wingspan of 0,7 to about 1 cm.
 Patrick Schmitz; Daniel Rubinoff: Ecologically and Morphologically Remarkable New Cosmet Moth Species of the Genus Hyposmocoma (Lepidoptera: Cosmopterigidae) Endemic to the Hawaiian Islands, with Reference to the Spectacular Diversity of Larval Cases. Annals of the Entomological Society of America 104(1): 1-15. 2011