About Thelymitra petrophila Jeanes
Thelymitra petrophila is a tuberous, perennial herb. It produces a single erect, leathery, channelled, glaucous, light green leaf that is linear to lance-shaped, measuring 100โ600 mm (4โ20 in) long and 4โ12 mm (0.2โ0.5 in) wide. Between two and ten or more pale blue to mauve or pink flowers, each 20โ30 mm (0.8โ1 in) wide, grow arranged along a flowering stem that is 100โ700 mm (4โ30 in) tall. The sepals and petals of the flowers are 10โ15 mm (0.4โ0.6 in) long and 3โ8 mm (0.1โ0.3 in) wide. The central column of the flower is white to pale blue or pale pink, 5โ7 mm (0.2โ0.3 in) long and 2โ4 mm (0.08โ0.2 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 bear toothbrush-like tufts of white hairs. Flowering occurs from August to November. This orchid, commonly called the granite sun orchid, grows in shallow soil pockets on granite outcrops. It occurs in the drier parts of Western Australia, including the Great Victoria Desert.