Ornduffia calthifolia

[1] The species only occurs in the granite peaks, outcrops and drainage lines of the Porongurup Range, in the Jarrah Forest IBRA bioregion of Southwest Australia, mainly above an altitude of 400 m. There the plants occupy moist, shady positions in rock crevices and beneath overhangs.

The soils are shallow sandy loams, containing accumulated organic material, that have water percolating through them in winter.

[1][3] The species has a restricted area of occurrence and limited population size, and is listed as Endangered under Australia's EPBC Act.

The main threats include habitat degradation by invasive weeds and grazing by herbivores such as rabbits and western grey kangaroos.

[1] Another potential threat is hybridisation with the closely related Ornduffia marchantii, which has a similarly restricted range, though mostly at lower elevations, within the Porongurups.