The Kauai cave amphipod (Spelaeorchestia koloana) is an obligate cave-dwelling arthropod restricted to the Hawaiian island of Kauai. It has only been found in the Koloa Basin of the island of Kauai where lava tubes and other cave bearing rock are present. Frank Howarth discovered the Kauai cave amphipod (Spelaeorchestia koloana ) along with the Kauai cave wolf spider in Koloa Cave 2 in 1971. Because of the unusual attributes of a highly reduced pincher-like condition of the first gnathopod (cephalothoracic appendage) and the second gnathopod being mitten-like in both sexes, this taxon is placed in its own unique genus (Spelaeorchestia) within the family Talitridae (Bousfield and Howarth 1976). This species is also distinctive in its lack of eye facets and pigment, and extremely elongate, spiny, postcephalic appendages. Adult amphipods are 7 to 10 millimeters (0.25 to 0.4 inches) in length and very slender-bodied, with a hyaline cuticle. Gnathopod 1 is highly reduced and gnathopod 2 is mitten-like. Antenna 2 is slender and elongate, with the flagellum only slightly longer than the peduncle. Peraeopods (abdominal walking legs) are very elongate, with slender, attenuated claws. All pleopods (swimming legs) are reduced, with branches vestigial or lacking. Uropods (tail-like appendages) 1 and 2 have well developed prepeduncles, and brood plates in the mature female are vestigial or entirely absent. The Kauai cave amphipod is a detritivore and has been observed feeding on rotting roots of Pithecellobium dulce (Manila tamarind) and Ficus sp. (fig), rotting sticks, branches and other plant material washed into the caves, and arthropod fecal material. In large cave passages, most individuals are found on or underneath roots or rotting debris. However, this amphipod does not appear to be particularly gregarious. When disturbed, this species typically moves slowly away rather than jumping like other amphipods. Nothing is known of the reproductive biology of this amphipod, but the vestigial brood plates of the female suggest they give birth to a small brood of large offspring (Bousfield and Howarth 1976; Poulson and White 1969).