Caladenia × triangularis, commonly known as the shy spider orchid, is a plant in the orchid family Orchidaceae and is endemic to the south-west of Western Australia. It has a single hairy leaf and up to three pale yellow flowers. A natural hybrid between flava and C. longicauda, it is a rare species found between Perth and Esperance.
Caladenia × triangularis is a terrestrial, perennial, deciduous, herb with an underground tuber and a single hairy leaf, 50–100 mm (2–4 in) long and 5–10 mm (0.2–0.4 in) wide. Up to three pale yellow flowers 50–70 mm (2–3 in) wide are borne on a spike 100–250 mm (4–10 in) tall. The petals and lateral sepals spread widely apart and the labellum is relatively small with a short fringe and four or more rows of calli along its mid-line. Flowering occurs from August to October.[2]
Caladeni × triangularis was first formally described 1827 by Richard Sanders Rogers from a specimen collected between Wagin and Narrogin. The description was published in Transactions and Proceedings of the Royal Society of South Australia.[3][4] The epithet (triangularis) refers to the shape of the labellum of this orchid.[2]
The shy spider orchid grows in woodland and shrubland between Perth and Esperance in the Avon Wheatbelt and Jarrah Forest biogeographic regions.[2][5]
Caladenia × triangularis is classified as "Priority Four" by the Government of Western Australia Department of Parks and Wildlife,[5] meaning that is rare or near threatened.[6]
Caladenia × triangularis, commonly known as the shy spider orchid, is a plant in the orchid family Orchidaceae and is endemic to the south-west of Western Australia. It has a single hairy leaf and up to three pale yellow flowers. A natural hybrid between flava and C. longicauda, it is a rare species found between Perth and Esperance.