More than 8,250 species of vascular plants, of which at least 26 percent are endemic, have been recorded in this hotspot. Three families occur nowhere else in the world (Doryanthaceae and the monotypic Austrobaileyaceae and Petermanniaceae). This high level of plant endemism at the family level places the hotspot third in this category among all hotspots.
The hotspot is home to the Critically Endangered Wollemi pine (Wollemia nobilis), found in the Blue Mountains' Wollemi National Park. The species is considered a living fossil, with all other members of its genus extinct for more than 2 million years.
A total of 28 out of 549 bird species in the hotspot are considered endemic. The colorful paradise parrot (Psephotus pulcherrimus) was likely endemic to the hotspot, but is considered Extinct, with the last sighting in 1927. The cause of extinction is unknown, but contributing factors may have included trapping and egg collection, disease, predation by introduced mammals, changes to the fire regime, and reduction of food supply due to overgrazing and land clearing.
Reptile endemism in the hotspot is 27 percent. One endemic reptile, the rain forest-dwelling Boyd's forest dragon (Hypsilurus boydii), is unusual in that its body temperature is generally within one degree of the air temperature.
Of vertebrate species in the hotspot, amphibian species endemism is the highest (32 percent). However, there have been several amphibian extinctions in the recent past, notably the two remarkable species of gastric-brooding frog. More hopeful is the story of the Critically Endangered yellow-spotted tree frog (Litoria castanea). The species had not been sighted since 1980, and widely thought to be extinct. However, in 2009, a population of about 100 was found.
It is estimated that well over 80 freshwater fish species are present in the hotspot, more than 10 of which are endemic. These numbers are almost certainly underestimates, and further analysis of freshwater fish data using finer-scale basin data is needed to generate a more accurate estimate of diversity and endemism within the hotspot's boundaries.