Variabilidade fenotípica e genotípica do camarão Macrobrachium jelskii (Miers, 1877) das Bacias do Nordeste Brasileiro: uma abordagem de sistemática integrativa

摘要

Macrobrachium jelskii is a widely distributed species in northeastern Brazil, occurringthroughout South America. However, no studies on phylogeography, local morphologicalvariations and genetic variability of the populations of this species were carried out. Thisprawn species can reveal important information on the dispersion pattern and relatedvicariates for scenarios of past tectonic arrangements and other events that haveinfluenced the biogeography of the aquatic taxa. The aim of this manuscript is toinvestigate a phenotypic and molecular diversity of the prawn M. jelskii populations inthe Mid-Northeast Caatinga, Maranho Piauí and São Francisco ecoregions, influenced bypast scenarios and environmental local responses. This scientific article uses an approachof Integrative Systematics, a multivariate geometric morphometry, phylogenetic analyzesand genetic structuring. Geometric morphometry showed evident sexual dimorphism, inwhich females presented cephalothorax and abdomen more horizontally stretched. Thispossibly favors gonadal development, vitellogenesis and egg storage. Abstraction of theshape of the three body planes does not demonstrate a consensus on the structuring of thepopulations between M. jelskii in the Northeast of Brazil. This fact corroborates a lownucleotide and haplotype diversity, in which only one haplotype was shared among thepopulations of the basins. Thus, ratifying a possibility of introduction in the Northeastarea by DNOCS. In addition, the genetic data reported a presence of noises and doublepeaks not electropherogram, which represents co-amplification of mitochondrialpseudogenes of the region Cytochrome Oxidase I, little reported in the literature for thegenus Macrobrachium. This fact show a precedent of mistrust for published phylogeneticand phylogeographic relationships, which recently did not depict this. Knowing that thischaracteristic can generate an overestimation of evolutionary lineages and, thus,erroneous conclusions on dispersive, vicarious or speciation events, it is of importance toreport the cases of pseudogenes and the use of specific molecular primers for each taxon.