Hawaiian Subregion

a subregion of the Australian zoogeographic terrestrial region. It occupies the Hawaiian Islands, whose origins are volcanic.

Since the Hawaiian Islands were never connected to the mainland and are very distant from America and Asia, their fauna includes the most typical examples of island fauna. In its origins, most of the fauna of the Hawaiian subregion is similar to that of Polynesia (reptiles) and to some extent, of America (birds). There are no native terrestrial mammals; however, there are several species that were brought to the islands by accident (the rat and house mouse) or for acclimatization (the mongoose). There is one species of bat (of the American genus Lasiurus). A particular species of monk seal is found on the seacoast. In addition to the oceanic birds living along the shores and the wintering terrestrial birds, there are about 40 genera of permanent, nesting, terrestrial birds. Hawaiian Drepanididae are of particular interest as an example of speciation on islands. There are four endemic bird species of other families—the goose, duck, thrush, and flycatcher. Reptiles are represented by geckoes (primarily of the genera Hemidactylus and Lepidodactylus) and skinks (of the genera Ablepharus and Lygosoma), of which all nine species—as well as one species of freshwater turtle—were brought to the subregion. There are no snakes (with the exception of one imported type), crocodiles, or land tortoises. The Hawaiian subregion has eight species of amphibians (one species of toad and seven species of frogs), all imported. Freshwater fish belong to ocean families. Insects, with the exception of beetles, are poorly represented: of 3,325 species, about 2,700 are found only on the Hawaiian Islands. Of 200 species of stinging insects of the order Hymenoptera, 170 are endemic. There are only several dozen species of diurnal butterflies, including species from the tortoiseshell, blue, and Anosia genera. The Hawaiian subregion has about 400 species of mollusks, all of which are native; the majority of them (14 genera including more than 300 species) belong to the endemic family Achatinellidae.