[2][1] The fossils from Barbers Point consisted of a single, incomplete skeleton (USNM 386435) that included a partial skull, mandible, and several postcranial elements that were found on the floor of the cavern near a specimen of the related Corvus impluviatus.

C. moriorum, another Corvus species, has a larger cranial fenestra, less ossified nasal cavities, shallower mandibular ramus, and a smaller articular mandible end than C. viriosus.

C. viriosus is like C. hawaiiensis but differs from C. impluviatus in that it has a narrower dorsal nasal bar, a slimmer zygomatic process, a stouter olecranon on the humerus, and a shorter posterior projection on the ilium.

The lower parts of the islands were much drier and had their own distinct flora and fauna, but many of the native species that lived in the lowlands have gone extinct due to human colonization.

[7][3] Although hunting by humans and imported animals played a role, the destruction of habitats by Polynesians, usually by fire, to make space for agriculture was likely the cardinal factor in the species’ extinction.

[9][8] At the site of the holotype's discovery in Barbers Point, Oahu, charcoal from a hearth and fossils of several animals that had been imported such as bones of the Pacific rat and shells from land snails were unearthed and dated to as recently as 770 CE.