McFarlane et al. 2011 Speleobiology Notes 3: 11-18 11 New Records of Crabs from the Caves of Gunung Mulu National Park, Sarawak, with a field key to the cavernicolous taxa of Northern Sarawak Donald McFarlane 1 , Joyce Lundberg 2 , and Keith Christenson 3 1 Wm. Keck Science Center, Scripps College, 925 North Mills Avenue, Claremont, CA 91711 USA. dmcfarlane@jsd.claremont.edu 2 Department of Geography and Environmental Studies, Carleton University, Ottawa, K1S 5B6, Canada. joyce_lundberg@carleton.ca 3 4111 Mountain Pass Road, Troutville, VA 24175, USA. tropicalbats@hotmail.com Key Words: Malaysia; Sarawak, Gunung Mulu, Borneo, cave, crab, Decapoda. Freshwater crabs have undergone a significant radiation on the island of Borneo, comprising four families (Potamidae, Geocarcinucidae, Parathelphusidae, and Sesarmidae), 15 genera and at least 49 species. The group is best known from the Malaysian state of Sarawak, primarily as a result of work by the Sarawak Museum, studies at Gunung Mulu National Park, and by Peter Ng of the University of Singapore and Raffles Biodiversity Center. Ten north- Borneo taxa are known to be cavernicolous, of which four are probably true troglobites. Two of these troglobitic crabs are known from caves of Gunung Mulu National Park, and one each from the smaller, non-contiguous massifs of Niah Great Cave National Park, Sarawak, and one from Simud Puteh Cave, Gomantong Forest Reserve, Sabah Figure 1. Location map, showing Gunung Mulu National Park, Sarawak. The shaded area shows the limestone massifs of Gunung Buda, Gunung Benerat, Gunung Api, and the Southern Hills. Fruit bat cave is located within the Southern Hills, in the informally named “Wild Boar Hill” marked by an arrow in this figure.