Thelymitra petrophila

Thelymitra petrophila is a tuberous, perennial herb with a single erect, leathery, channelled, glaucous, light green linear to lance-shaped leaf 100–600 mm (4–20 in) long, 4–12 mm (0.2–0.5 in) wide. Between two and ten or more pale blue to mauve or pink flowers 20–30 mm (0.8–1 in) wide are arranged on a flowering stem 100–700 mm (4–30 in) tall. The sepals and petals are 10–15 mm (0.4–0.6 in) long and 3–8 mm (0.1–0.3 in) wide. The column is white to pale blue or pale pink, 5–7 mm (0.2–0.3 in) long and 2–4 mm (0.08–0.2 in) wide. The lobe on the top of the anther is brown to reddish or yellow with an inflated tube shape and wavy edges. The side lobes have toothbrush-like tufts of white hairs. Flowering occurs from August to November.[2][3][4][5]

Thelymitra petrophila was first formally described in 2013 by Jeff Jeanes and the description was published in Muelleria from a specimen collected near Menzies.[6] The specific epithet (petrophila) is derived from the Ancient Greek πέτρα (pétra) meaning "rock" or "stone"[7]^: 601 and φίλος (phílos) meaning "dear" or "beloved"[7]^: 498 referring to the habitat preference of this species.[3]

The granite sun orchid grows in shallow soil pockets on granite outcrops. It is found in the drier parts of Western Australia, including the Great Victoria Desert.[2][3][8]