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.
List of islands in the Houtman Abrolhos
The Inventory of the Land Conservation Values of the Houtman Abrolhos mentions many more unofficially named islets, 16 in the Wallabi Group, 26 in the Eastern Group and 15 in the Pelsaert Group, plus the subgroups of the Jackson Islets (7 islets without individual names or numbers) and The Coral Patches (13 islets without individual names or numbers), also in the Pelsaert Group.