Understanding Distributions of Poorly Known Species Marinez Ferreira de Siqueira Centro de Referência em Informação Ambiental

Poorly Known Species Microendemics or rare Poorly collected species Species with extremely restricted ecological needs E.g., in Cerrado vegetation, 30% of trees are known from single records in the Projeto de Cooperação Técnica Conservação e Manejo da Biodiversidade do Bioma Cerrado – EMBRAPA Cerrados – UnB – Ibama/DFID e RBGE/Reino Unido database What to do to understand (or begin to understand) the distributions of these species?

Ecological Space Measure distance in ecological space Position of point that might be adjacent to known occurrence Annual Mean Temperature Available Environments Position of point from which species is known Annual Mean Precipitation

Measure Ecological Similarity Across Landscape Measure ecological distances from all points

Understanding Distributions of Poorly Known Species The idea is to characterize the landscape and region surrounding the one known occurrence as to how similar or different it is in terms of ecological parameters.

Assis Ecological Station, a Conservation Unit in São Paulo State. Results of modeling for Byrsonima subterranea Brad. & Mark. (Malpighiaceae) Assis Ecological Station, a Conservation Unit in São Paulo State.

Modeling for Byrsonima subterranea grey area = less environmental similarity blue area = high environmental similarity

Modeling for Byrsonima subterranea Identify areas of high and low ecological similarity to known occurrence point Black = patches of the cerrado vegetation type

Modeling for Baccharis pseudotenuifolia

Understanding Distributions of Poorly Known Species To test the applicability of this approach, we will go to the field to assess whether additional occurrences of this species are concentrated in areas that are highly similar to the single known locality. This approach is highly experimental, and its presentation at this point is quite preliminary, but it is an illustration of potential approaches to understanding better even the most poorly known species

Acknowledgments Prof. Dr. A. Townsend Peterson - Natural History Museum and Biodiversity Research Center, The University of Kansas, to help with modelling Dra Giselda Durigan - Assis Ecological Station