The isolation of high montane / sub-alpine habitats on Mt Canobolas has captured outliers of numerous species, known from other areas of the State but finding their limits in or around the SCA. Such isolated populations evolve independently and may potentially form new species.
In addition to the threatened and endemic species, the biota of the SCA is noteworthy for the many regionally significant species that are rare or at the limits of their natural geographic ranges. Range edges are characterized by increased genetic isolation, genetic differentiation, and variability in individual and population performance so are important for conservation.
One hundred and sixty eight species, around 21%, of the known biota, are at their range limit on or in close proximity to the mountain. The majority of these are among the fungi and vascular plants, however for most of the invertebrate taxa, there isn’t sufficient information to determine their status in this context. A small number of species, four plants and two fungi are northern species which occur at their southernmost range limits around or on the mountain. A larger number, 16 fungi and 21 plant species are clearly species with their distributional strongholds in southern regions, being at their northernmost range limit on or near the mountain. Many of these species have strong alpine affinities. The greatest number, 25 fungi and 75 plant species are at their westernmost distribution within the Central West of NSW. These are comprised of many coastal and Blue Mountains species.
Terrestrial orchids are another subset of plants with regional significance within the SCA. At least 35 species are known to occur, making the mountain important for conservation of these species which are declining elsewhere through loss of habitat. A fire ephemeral Prasophyllum sp., only seen after a summer fire in 1982, is endemic and other orchid species are at their geographic range limits.