Abstract
The Cabeça do Cachorro region (or Tsiino Hiiwiida, in the Baniwa language) of the Upper Rio Negro in Brazilian Amazonia is a last global frontier of untapped biodiversity knowledge. The spatially complex arrangement of habitats in the region, including archipelagos of white-sand forests within a matrix of black-water, upland, and montane forests, is a major 'theatre' for evolution over mi…