Native species in Hawaii: 0
Introduced species: 1
If you live in Hawaii long enough and you root around in your gardens frequently enough, you're bound to see an Brahminy Blind Snake (Ramphotyhlops braminus). If you do ever happen to catch glimpse of these worm-looking vertebrates, you'll be know they are female. Its the only known parthenogenic snake. That means that one snake can populate an island by laying unfertilized eggs that hatch to become virtual female clones. Its a great adaptation that has enabled island existence of other species (notably the geckos).
Sometime in the 1980's the blind snake was introduced to the islands of Hawaii in potting soil from plants (probably from the Philippines). These small snakes with tiny eye-spots, eat small termites, ants and other arthropods. As termites and ants are also introduced animals, these snakes pose no great threat to ecosystems in Hawaii.
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