Houtman Abrolhos
The Houtman Abrolhos is unusual in having a luxuriant and diverse living coral reef at such a high latitude. 194 species in 50 genera have been recorded there, all but two of which are tropical. This is a surprisingly high coral diversity, considering the high latitude of the reef, and the relatively low diversity of other biota. For a full list, see list of corals of the Houtman Abrolhos.
Pelsaert Group
The Pelsaert Group is the southernmost of the three groups of islands that make up the Houtman Abrolhos island chain. Nominally located at , it consists of a number of islands, the largest of which are Gun Island, Middle Island, and Pelsaert Island. The group is named after a Dutch "opperkoopman" who stranded nearby with the VOC-ship "Batavia" in 1629. The group contains the most southerly true coral reefs in the Indian Ocean. The group is part of the Houtman Abrolhos Important Bird Area, identified as such by BirdLife International because of its importance for supporting large numbers of breeding seabirds.