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Where does Wallace’s Line run in Southeast Asia?

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World map using color coding to show the distribution of major floral kingdoms, subkingdoms, and regions. Key floral kingdoms include Boreal (green), Neotropical (pink), Paleotropical (yellow), South African or Capensic (purple), Australian (orange), and Antarctic (blue). Boundaries for subkingdoms, regions, and divisions are marked with different colored lines, and major regions such as Indoafrican, North American, and Malesian are labeled across continents. — biogeographic region Floral kingdoms, subkingdoms, and major regions of the world.

The Wallace Line is a faunal boundary that separates the Oriental and Australian biogeographic regions. It runs through Southeast Asia along the following path:

It begins in the Indian Ocean and passes through the Lombok Strait, which lies between the islands of Bali and Lombok.12
It continues northward through the Makassar Strait, situated between Borneo and Celebes (Sulawesi).12
Finally, it extends eastward, passing south of Mindanao into the Philippine Sea.12

While modern zoogeographers often debate its status as a definitive regional boundary, the line remains significant for marking an abrupt limit in the distribution of many major animal groups, including various mammals, birds, and fish.1