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We investigated the utility of nuclear and cytoplasmic single nucleotide polymorphism (SNP) markers for timber tracking of the intensively logged and commercialized Amazonian tree Jacaranda copaia. Eight hundred and thirty-two trees were sampled (cambium or leaves) from 38 sampling sites in Bolivia, Brazil, French Guiana, and Peru. A total of 128 SNP markers (113 nuclear, 11 chloroplastic, and 4 mitochondrial) were used for genotyping the samples. Bayesian cluster analyses were carried out to group individuals into homogeneous genetic groups for tests to self-assign groups of individuals or individuals to their population of origin. Cluster analysis based on all the SNP markers detected seven main genetic groups. Genetic differentiation was high among populations (0.484) and among genetic groups (0.415), and populations showed a strong isolation-by-distance pattern. Self-assignment testing of the groups of individuals for all loci was able to determine the population origin of all the samples (accuracy = 100%). Self-assignment tests of individuals were able to assign the origin of 94.5%–100% of individuals (accuracy: 91.7%–100%). Our results show that the use of the 128 SNP markers is suitable to correctly determine the origin of J. copaia timber, and they should be considered a useful tool for customs and local and international police.

This Special Issue presents recent advancements in tropical dendrochronology in the tropical and subtropical Americas, focusing on the identification of new species for dendrochronological studies, the assessment of climate information contained in tree-ring records, and systematic reviews of past research. The studies included in this issue significantly contribute to our understanding of tree species suitable for dendrochronology and the improvement of dating techniques. Moreover, they delve into the relationships between climate variables and tree growth, offering insights into the response of tropical forests to environmental change and providing tools for reconstructing past climate conditions. These studies also shed light on the challenges associated with accurately distinguishing annual ring boundaries in tropical species with complex anatomical structures and emphasize the importance of integrating complementary dating methods and visualization techniques to enhance the reliability of dendrochronological studies in the tropics. By synthesizing diverse research findings, this Special Issue offers a comprehensive overview of tropical dendrochronology in the American (sub) tropics, revealing gaps in knowledge, and suggesting potential avenues for future research. Ultimately, these advancements promote a deeper understanding of tropical forests, their role in the global climate system, and the need for their sustainable management and conservation.