Understanding molecular relationships in Campomanesia Ruiz & Pav. (Myrtaceae): emphasizing the C. xanthocarpa complex based on multiple accessions

Campomanesia comprises approximately 45 species, and 18 of them are organized into three informal morphological complexes. Among these, the "C. xanthocarpa complex" includes nine accepted species displaying delimitation problems, especially in C. adamantium (Cambess.) O.Berg, C. eugenioides (Cambes.) D.Legrand ex Landrum and C. xanthocarpa (Mart.) O.Berg. As there are no phylogenies available for the genus, we seek to understand whether the morphological similarities observed between the cited taxa may be congruent with molecular data. Thus, we generated sequences of the internal transcribed spacer of the ribosomal nuclear DNA (ITS) from 32 samples of Campomanesia and nine belonging to other genera of neotropical Myrtaceae. Phylogenetic analyses using Maximum Parsimony and Bayesian Inference produced similar topologies, which indicate that the "C. xanthocarpa complex" is not monophyletic. Otherwise, the taxa previously assigned to this complex correspond to two distinct lineages highly supported, here designated as the "C. xanthocarpa Group" and "C. eugenioides Group." The use of multiple accessions of these species also provided taxonomic insights for the recognition of C. littoralis D.Legand and C. repanda O.Berg, as well as the separation of C. rhombea from C. xanthocarpa.