Varanus obor, popularly referred to as Torch monitor and Sago monitor, has a bright orange head with a glossy black body. It is a close relative of the fruit-eating monitor lizard recently reported from the Philippines. The Torch monitor can grow to nearly four feet in length, and thrives on a diet of small animals and carrion.
The Torch monitor exists only on the small island of Sanana in the western Moluccan islands, which uniquely lacks mammalian predators, a factor that may have given reptiles the space to evolve as the top terrestrial predators and scavengers.
Several million years ago, this island was situated near New Guinea, and it is possible that the lizard lives on as a relic from that period. It is the only black monitor in its lineage, and the only monitor species anywhere that has evolved red pigmentation.
"East of Wallace's Line –– the boundary between Asian and Australian domains –– there are no native carnivorous mammals, and monitor lizards fill that role. There are more species there, doing more different things ecologically than in Africa or South and Southeast Asia, where competition and predation by mammals tend to keep monitor lizards down," said Sam Sweet, a biologist at UCSB. "East of Wallace's Line in Indonesia, New Guinea, and Australia, monitor lizards are on the top of the heap.