• Premise of the study: Microsatellite loci were developed for tucumã of Amazonas (Astrocaryum aculeatum), and cross‐species amplification was performed in six other Arecaceae, to investigate genetic diversity and population structure and to provide support for natural populations management.• Methods and Results: Fourteen microsatellite loci were isolated from a microsatellite‐enriched genomic library and used to characterize two wild populations of tucumã of Amazonas (Manaus and Manicoré cities). The investigated loci displayed high polymorphism for both A. aculeatum populations, with a mean observed heterozygosity of 0.498. Amplification rates ranging from 50% to 93% were found for four Astrocaryum species and two additional species of Arecaceae.• Conclusions: The information derived from the microsatellite markers developed here provides significant gains in conserved allelic richness and supports the implementation of several molecular breeding strategies for the Amazonian tucumã.

The large catfish Pseudoplatystoma punctifer has a high commercial value in the Amazon. Fifteen polymorphic microsatellite loci were isolated and characterized in 36-39 individuals of this species sampled at the Purus river (Amazon Basin). The number of alleles per locus ranged from 2 to 18 (average 7.4), the observed heterozygosity (H O ) from 0.025 to 0.972 and the expected heterozygosity (H E ) from 0.025 to 0.931. Two loci showed a Hardy-Weinberg Equilibrium deviation. No linkage disequilibrium was found among the studied loci. Fourteen microsatellite loci were cross-amplified successfully in six other Pimelodidae species. Therefore, these loci may be valuable for other studies of population genetic structure as well as for catfish conservation in the Amazon basin.