Eriochilus, commonly known as bunny orchids, is a genus of flowering plants in the family Orchidaceae (order Asparagales), endemic to Australia. The genus was first formally described in 1810 by the botanist Robert Brown in his Prodromus Florae Novae Hollandiae. Around 17–20 species are currently recognised, distributed across south-west Western Australia, South Australia, Queensland, New South Wales, the Australian Capital Territory, Victoria, and Tasmania.
Plants in this genus are terrestrial, perennial, deciduous, and sympodial herbs. They grow from a roughly spherical, succulent tuber, with replacement tubers forming at the end of short underground "droppers." Each plant produces a single glabrous (hairless) leaf that is egg-shaped to lance-shaped, arising either at the base or along the flowering stem. This hairless leaf is one of the key features distinguishing Eriochilus from the closely related genus Caladenia.
The inflorescence is a raceme bearing up to 25 resupinate flowers. The dorsal sepal is smaller and hood-like, curving forward over the labellum, while the lateral sepals are much longer, broader, white to pink, and spreading — resembling rabbit ears, hence the common name. The labellum, which is one modified petal, is densely covered with glandular hairs (giving the genus its name, from the Greek for "woolly lip") and is often spotted. Its base forms a tube around the lower column. The remaining two petals are smaller and narrower than the sepals. Flowers appear from late winter to early summer depending on the species. Fruits are non-fleshy dehiscent capsules containing up to 500 seeds.
Notable members include Eriochilus cucullatus (parson's bands), one of the most widespread species occurring across multiple eastern and southern states, and Eriochilus dilatatus, a Western Australian species with several named subspecies including the common bunny orchid, Easter bunny orchid, and white bunny orchid.
Etymology
The genus name Eriochilus is formed from the Ancient Greek ἔριον (erion, "wool") and χεῖλος (cheilos, "lip"), a direct reference to the densely hairy labellum that characterises these orchids. The popular common name "bunny orchids" alludes to the prominent, ear-like lateral sepals of the flowers.
Distribution
Bunny orchids are endemic to Australia. The greatest species diversity occurs in south-west Western Australia, where ten species are found in habitats ranging from winter-swampy ground to dry inland woodlands, spanning from north of Kalbarri to Israelite Bay on the south coast. Three species occur in South Australia (including the Eyre and Yorke Peninsulas), with additional species in Victoria, New South Wales, Queensland, the Australian Capital Territory, and Tasmania.
Taxonomy Notes
The genus was first formally described in 1810 by Robert Brown and published in Prodromus Florae Novae Hollandiae et Insulae Van Diemen. Eriochilus is placed in the family Orchidaceae, order Asparagales. It is closely allied to Caladenia, from which it is distinguished primarily by its glabrous (hairless) leaf and the densely woolly labellum. Plants of the World Online recognised approximately 17 species and additional subspecies as of April 2025.
