Accepted by P. Perkins: 8 Jun. 2010; published: 24 Jun. 2010 33 ZOOTAXA ISSN 1175-5326 (print edition) ISSN 1175-5334 (online edition) Copyright © 2010 · Magnolia Press Zootaxa 2517: 33–43 (2010) www.mapress.com/ zootaxa/ Article The genus Portelmis Sanderson, 1953 (Coleoptera: Elmidae: Elminae): first report in Brazil, description of two new Amazonian species and species key for males ANDRÉ S. FERNANDES 1, 4 , MARIA INÊS S. PASSOS 2 & NEUSA HAMADA 3 1 Instituto de Pesquisas Ambientais e Ações Conservacionistas, CEP: 74805-370, Goiânia, GO, Brazil. E-mail: andrelmis@gmail.com 2 Universidade Federal do Estado do Rio de Janeiro, Departamento de Zoologia. Av. Pasteur, 458 – 4. andar, CEP: 22290-240, Rio de Janeiro, RJ, Brazil. E-mail: minespassos@gmail.com 3 Instituto Nacional de Pesquisas da Amazônia, Divisão de Curso em Entomologia, Coordenação de Pesquisas em Entomologia, Caixa Postal 478, CEP: 69011-970 Manaus, AM, Brazil. E-mail: nhamada@inpa.gov.br 4 Corresponding author Abstract The genus Portelmis Sanderson, 1953 and the species P. gurneyi Spangler, 1980 are reported for the first time in Brazil. Portelmis kinonatilis sp. nov. and P. paulicruzi sp. nov. are described and illustrated based on adult specimens collected in two different municipalities in the state of Amazonas, Brazil. Diagnoses and illustrations of all Portelmis species, and a taxonomic key to identify males are presented. Key words: aquatic insects, kinon, Neotropics, Portelmis, riffle beetle, taxonomy Introduction The Neotropical genus Portelmis was established by Sanderson (1953) based on Stenelmis nevermanni Hinton, 1936, collected in Costa Rica. He analyzed this species and concluded that it should not be placed in the genus Stenelmis, based mainly in the presence of a patch of tomentum on the protibiae, that were not observed by Hinton (1936) in the original description of the species. Spangler (1980) described the second species of the genus, Portelmis gurneyi, collected in Ecuador (the first report of the genus for South America); he also reviewed the major characteristics differentiating P. gurneyi from P. nevermanni and added information about the type series of P. nevermanni not included in the original description. The Portelmis larva is still unknown. In this paper, we report the genus Portelmis and the species P. gurneyi for the first time in Brazil. We also describe and illustrate two new species in this genus that were collected in small streams in terra firme (upland) forest, in the state of Amazonas, Brazil. Diagnosis and illustrations of all Portelmis species and a taxonomic key to identify their males are presented. Material and methods The specimens analyzed in this study were collected in two municipalities in the state of Amazonas. In Coari municipality, specimens were collected using a D-net on the available substrates in the streams. In Presidente Figueiredo municipality, they were collected using light traps placed along the streams. Morphological terminology follows Brown (1972). Some of the specimens were dried and pinned, while the remaining specimens were preserved in 80% ethanol. Dissected genitalia were stored in microvials with glycerin and maintained with the same vial or pin as the body of the adult from which they were removed.