TECHNICAL NOTE Isolation and characterization of microsatellites loci for ‘‘piramutaba’’ (Brachyplatystoma vaillantii, Siluriformes: Pimelodidae), one of the commercially most important migratory catfishes in the Amazon Basin Fabiola C. Rodrigues Æ Izeni P. Farias Æ Jacqueline S. Batista Æ Jose ´ Alves-Gomes Received: 14 August 2009 / Accepted: 20 August 2009 / Published online: 12 September 2009 Ó Springer Science+Business Media B.V. 2009 Abstract The piramutaba (Brachyplatystoma vaillantii) is one of the largest and most important migratory catfishes of the Amazon Basin. Due to its historical commercial importance, this species is now considered overfished. Fifteen polymorphic microsatellite markers were charac- terized in order to be used as tools to address aspects of the biology and conservation of this species. The number of alleles varied from 4 to 26 per locus, with an average of 11.33 alleles per locus, in 36–48 individuals tested. The observed and expected heterozygosities varied from 0.30176 to 0.95281, and from 0.25532 to 0.97778, respec- tively. All the microsatellites were found to be in Hardy– Weinberg equilibrium, and no linkage disequilibrium was observed. The transferability of these markers was tested in others Brachyplatystoma with seven to 12 loci being poly- morphic per species. The results indicate that these markers are adequate for genetic studies applied to the management and conservation of the piramutaba, and others Brachy- platystoma species. Keywords Piramutaba Á Microsatellites Á Brachyplatystoma vaillantii Á Migratory catfish Á Amazon Introduction The ‘‘piramutaba’’ (Brachyplatystoma vaillantii) is a large migratory catfish belonging to the Family Pimelodidae (Nelson 2006). In the course of its life cycle, the species makes long migrations for reproduction and preliminary genetic results indicate that a single stock inhabits the entire Amazonian Basin (Batista et al. 2004). The current hypothesis suggests that shoals of adults migrate upriver to spawn in the head waters of the white-water affluent of western Amazon Basin. The larvae are then carried downstream by the current towards the estuary which acts as a nursery and growth area. Upon reaching adulthood, the cycle is repeated (Barthem and Goulding 2007).This spe- cies occurs in greatest abundance in the main channel and the tributaries of the Solimo ˜es-Amazonas basin and in the mouth of the Amazonas River (Barthem and Goulding 1997). The piramutaba is one of the most commonly caught species by the industrial and artisanal fishing fleets in the Amazon. Its commerce encompass a great deal of inter- national trade, including several Amazonian countries and generates revenues amounting to several millions of dollars (Almeida 2006; Barthem and Goulding 2007). However, surveys of unloaded fish catches show that the piramutaba yield has been suffering a decline over the years and, in fact, evidence point to a progressive overfishing, as indi- cated by constant reductions in size commercialized (Alonso and Pirker 2005). In view of the fact that this species is an important source of income for thousands of F. C. Rodrigues Á J. S. Batista Á J. Alves-Gomes Laborato ´rio Tema ´tico de Biologia Molecular (LTBM), Instituto Nacional de Pesquisas da Amazo ˆnia, Av. Andre ´ Arau ´jo, No. 2936, CEP 69060-001 Manaus, AM, Brazil I. P. Farias (&) Laborato ´rio de Evoluc ¸a ˜o e Gene ´tica Animal, Departamento de Biologia, Universidade Federal do Amazonas, Av. Rodrigo Octa ´vio Jorda ˜o Ramos 3000, 69077-000 Manaus, AM, Brazil e-mail: izeni_farias@ufam.edu.br J. S. Batista Á J. Alves-Gomes Coordenac ¸a ˜o de Pesquisas em Biologia Aqua ´tica, Laborato ´rio de Fisiologia Comportamental e Evoluc ¸a ˜o (LFCE), Instituto Nacional de Pesquisas da Amazo ˆnia, Av. Andre ´ Arau ´jo, No. 2936, CEP 69060-001 Manaus, AM, Brazil 123 Conservation Genet Resour (2009) 1:365–368 DOI 10.1007/s12686-009-9084-x