Carabdytes plantaris is a naturally uncommon species of diving beetle in the family Dytiscidae.

For over a century, it was known from just a single specimen collected in 1880 "near Dunedin", and doubts were cast on whether it was actually a New Zealand species at all.

In 1986, it was rediscovered when several were collected from a roadside pond near Lake Ellesmere.

[1] Carabdytes plantaris is now classed as "naturally uncommon" by the Department of Conservation.

[2] This species was formerly a member of the genus Rhantus.