Australasian realm

The Australasian realm is a biogeographic realm that is coincident with, but not (by some definitions) the same as, the geographical region of Australasia. The realm includes Australia, the island of New Guinea (comprising Papua New Guinea and the Indonesian province of Papua), and the eastern part of the Indonesian archipelago, including the island of Sulawesi, the Moluccas (the Indonesian provinces of Maluku and North Maluku), and the islands of Lombok, Sumbawa, Sumba, Flores, and Timor, often known as the Lesser Sundas. The Australasian realm also includes several Pacific island groups, including the Bismarck Archipelago, Vanuatu, the Solomon Islands, and New Caledonia. New Zealand and its surrounding islands are a distinctive sub-region of the Australasian realm. The rest of Indonesia is part of the Indomalayan realm. In the classification scheme developed by Miklos Udvardy, New Guinea, New Caledonia, Solomon Islands and New Zealand are placed in the Oceanian realm. From an ecological perspective the Australasian realm is a distinct region, parts of which have a common geologic and evolutionary history. The entire area has experienced a long period of biological isolation from other regions, and thus harbors a great many unique plants and animals. In this context, Australasia is limited to Australia, New Guinea, New Zealand, New Caledonia, and neighbouring islands, including the Indonesian islands from Lombok and Sulawesi eastward. The Wallace Line to the west divides areas in the Indomalayan realm of tropical Asia which are or have at times been directly connected to the Asian mainland from islands that have never been so connected. Borneo and Bali lie on the western, Asian side. A second biological dividing line is Lydekker's Line, which similarly separates islands isolated by surrounding deep water from those associated with the Sahul Shelf of the Australian continent. Islands between the two lines (e.g.