Two new species of marmosets, squirrel-sized New World monkeys, have been identified in the heart of the Brazilian Amazon. Described in the March issue of Neotropical Primates, Dutch primatologist Marc van Roosmalen discovered the animals living as pets among the inhabitants of small riverbank settlements.
Callithrix manicorensis and Callithrix acariensis are both light-colored, with one having orange or yellow underparts and the other an orange-tipped black tail. Van Roosmalen, a primatologist at the National Institute for Amazon Research in Manaus, noticed the monkeys while doing fieldwork in the Rio Madeira basin, a remote area in northwestern Brazil, for Washington, D.C.-based Conservation International.
The discovery proves that "we are still far from understanding the biodiversity of most tropical organisms," says primatologist John Fleagle of the State University of New York, Stony Brook. The fact that scientists had completely missed the "brightly colored, diurnal mammals," he says, suggests that "the unknown diversity in small, less visible taxa must be vastly greater."
