14 May 2014 Dear Edilson Carvalho Siqueira, I am contacting you with regards to Daniel Pimpão. I have invited Daniel to participate on a collecting expedition to the lower rio Xingu. The expedition will take place in November 2014 and is composed three separate outings: 8 days in the rio Xingu below Vitória do Xingu, 5 days in Volta Grande, and 5 days in the rio Xingu above Altamira to the mouth of the rio Iriri. The expedition is part of a larger inventory funded by the US National Science Foundation (NSF). Dra. Lúcia Rapp Py-Daniel, Instituto Nacional de Pesquisas da Amazônia (INPA), is the Principal Brazilian Coordinator and I, Dr. Mark Sabaj Pérez, am the Principal Foreign Coordinator. Our project, entitled “LEVANTAMENTO DA BIOTA AQUÁTICA DO BAIXO RIO XINGU”, is authorized by the Ministério do Meio Ambiente, ICMBio, SISBIO via permit No. 39041-2 (valid 10 Feb 2014 to 12 Mar 2015), and published in the Diário Oficial da União, Portaria No. 366 (valid 28 Mar 2014 to 28 Mar 2016). The primary objective of the project is to assemble a complete inventory of the mollusks, crustaceans and fishes of the lower rio Xingu, and to place them in the context of the fauna of the Amazon basin using morphological and molecular data. To view all documents relevant to the authorization of our project, please visit: http://symbiont.ansp.org/ixingu/ To date we have completed two successful expeditions in October 2013, and March 2014. The third expedition, planned for November 2014, will complete the NSFfunded portion of the fieldwork. I am requesting permission for Daniel Pimpão to participate on a portion of the November expedition: 8 days in the rio Xingu below Vitória do Xingu. All expenses associated with his participation in fieldwork will be paid for by our grant from the US National Science Foundation. The lower Xingu is poorly sampled for mollusks, therefore its fauna is poorly known. Daniel has an excellent working knowledge of the mollusks, particularly bivalves, of the Amazon Basin. Such expertise is rare and would be extremely helpful to our project. His participation would be in collaboration with US malacologists working on the NSF-funded project, and serve to provide a complete and accurate inventory of the lower Xingu fauna. I hope you will consider my request for Daniel Pimpão to participate in fieldwork and the mollusk studies associated with our project. Please do not hesitate to contact me for further information. Sincerely, Dr. Mark Sabaj Pérez Co-Principal Investigator, iXingu Project, NSF DEB-1257813