Orchids belong to the second world’s largest family of flowering plants, which comprises 736 currently recognized genera, and nearly 28,000 species (Chase, Cameron et al. 2015). Among them is the Red Helmet Orchid, a rare terrestrial colonially growing tuberous herb, also known as Red Lantern. C. dowlingii is endemic to Australia and believed to be confined only to New South Wales, where it has so far been found at two localities in Port Stephens, plus two additional sites near Bulahdelah, and Freemans Waterhole, south of Newcastle (Okada 2006).
Documented occurrences (about 18,400 plants) cover <1,000 Km2 of land in total; however, with the exception of Port Stephens (≈50 ha), all reported populations occupy areas of less than a few hectares each. No occurrence has been found within existing conservation reserves. Rather, clearing, illegal dumping, habitat degradation and fragmentation, and anthropogenic disturbance are major factors, contributing to a steady decline in numbers (Okada 2006).
We performed species distribution modelling (SDM) with MaxEnt (Phillips, Anderson et al. 2006) to model the C. dowlingii’s fundamental niche, across most NSW coastal area and eastern Victoria. Habitat suitability prediction was based on environmental predictors like soil properties, and gridded conformal datasets of spatially-interpolated monthly climate data, averaged between 1970-2000, at high spatial resolution (≈1 Km2) (Fick and Hijmans 2017).