The use of actual topotypes to produce genotypes and cytotypes in the taxonomic review of the Mazama genus: the basis for the species conservation

Abstract

Brocket deer species, Mazama genus, are known as a group of mammals with important taxonomic issues. Mostly, this is due to a high level of homoplasy of morphological characters and high karyotyping diversity. These characteristics suggests that there are still many species to be described, once karyotyping differences among populations generates post-zygotic reproductive barriers. In order to re-describe the species it is necessary to collect specimens at the type localities where each genus name were previously described in a sense of verifying its genetics and morphological constitution and the presence of chromosomal barriers and molecular structure. For these purposes, specimens will be collected at the type localities (new topotypes) of each of the available name, that are considered today a synonymous of known species. Helped by local teams, about 45 specimens will be collected at 16 countries following a chronological sequences of the publications in order to verify its validity. Skin and testis fragments, frozen in liquid nitrogen, will be collected. Also, samples of liver, kidneys, spleen and muscles will be collected and preserved in absolute ethanol. All the bones will be cleaned and conserved as dried specimens. The skin will be treated with a tannery solution for deposition in scientific collection. The specimens will be evaluated cytogenetically (chromosomal biometry, G band, C band, NOR band, telomeric FISH and chromosomal paint), molecularly (Cytochrome B, D-Loop, ND5, COI, α-LAlb, IL16, MGF) and morphologically (biometry, skull, post-skull, skin and photographs) and compared with patterns previously obtained for the older names. Sperm FISH experiments of gametic segregation will be carried out to evaluate the thresholds of the chromosomal differences that became efficient reproductive barriers. From this point, that threshold will be considered to describe distinct species. Moreover, methodological studies will be developed to evaluate hair samples as a potential non-invasive biological matrix for morphology, cytogenetics and molecular genetics. Also, the species group speciation process will have an ecological approach to understand the micro and macro environmental niche dimensions overlap among well-established species. With the scientific advance intended with this project it is expected to give sustainability to the IUCN threatened categorizations process contributing to unknown or neglected species conservation. Also, it is expected to strengthen the cervidology of Latin America with technology exchange among the established research groups and creation of new groups in countries where this research field is incipient. (AU)