Catasetum cantuariae (Orchidaceae, Catasetinae), a new species from the Brazilian Amazonian biome

In this article we propose a new Catasetum species which presents affinity to the C. cristatum alliance, more specifically to species belonging to the C. barbatum complex. The new species has been found in the flooded forests of the Nhamundá River which constitutes the interstate limit between the States of Amazonas and Pará in Brazil. Plants were collected in flooded forest on the river’s left bank, in the municipality of Faro (Pará State, Brazil). The new species is here described in detail and data on habitat, distribution, phenology, conservation status are presented, along with photographs. The new species is compared to C. garnettianum, C. nhamundaense and C. barbatum, from which it differs mainly in the lip structure. All of these allied species are part of the Catasetum barbatum species complex. We also provide an identification key for Catasetum species from the C. barbatum complex occurring in the Brazilian Amazon.