Microsorum pustulatum (kangaroo fern or hound's tongue, in Māori: kōwaowao, pāraharaha) is a species of fern within the Polypodiaceae family. This species occurs widely in New Zealand and also in Queensland, New South Wales, Victoria and Tasmania in Australia. An example occurrence in the North Island of New Zealand is in the Hamilton Ecological District where it is associated with a number of other ferns including Blechnum filiforme and Blechnum discolor.