Kidney fern, Trichomanes reniforme, is a filmy fern species native to New Zealand

New Zealand

New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

. It commonly grows on the forest floor of open native bush. Individual kidney-shaped ferns stand about 5-10 cm tall. In hot weather they shrivel up to conserve moisture, but open up again when the wet returns. This species has very thin fronds which are only four to six cells in thickness. In the Māori language

Maori language

Māori or te reo Māori , commonly te reo , is the language of the indigenous population of New Zealand, the Māori. It has the status of an official language in New Zealand...

 they are also called Raurenga.

A specific example of occurrence of T. reniforme is within forested areas of Westland

Westland District

Westland District is a territorial authority on the west coast of New Zealand's South Island. Its population is - Government :The Westland District is governed by an elected Council, headed by an elected Mayor. The Mayor is elected at large. The current Mayor is Maureen Pugh. Councillors are...

, New Zealand, where it occurs with other fern species including Crown Fern, Blechnum discolor

Blechnum discolor

Blechnum discolor is a species of fern in the family Blechnaceae. This species is endemic to New Zealand. As noted by C. Michael Hogan, this species is found in a number of forest communities in diverse locations within New Zealand, and is sometimes a dominant understory component.Spores are...