Weak premating isolation between two parapatric brocket deer species

Revalidation of Passalites Gloger, 1841 for the Amazon brown brocket deer P.nemorivagus (Cuvier, 1817) (Mammalia, Artiodactyla, Cervidae)

Mazamanemorivaga (Cuvier, 1817) is a gray brocket deer that inhabits the Amazon region. An assessment of previous studies revealed inconsistencies in its current taxonomic classification, suggesting the need for an update in its genus classification. A taxonomic repositioning of this species is proposed through the collection of a specimen from its type locality (French Guiana) with subsequent morphological (coloring pattern, body measurements, and craniometry), cytogenetics (G Band, C Band, conventional Giemsa, Ag-NOR staining, and BAC probe mapping), and molecular phylogenetic analysis (mitochondrial genes Cyt B of 920 bp, COI I of 658 bp, D-loop 610 bp), and comparisons with other specimens of the same taxon, as well as other Neotropical deer species. The morphological and cytogenetic differences between this and other Neotropical Cervidae confirm the taxon as a unique and valid species. The phylogenetic analysis evidenced the basal position of the M.nemorivaga specimens within the Blastocerina clade. This shows early diversification and wide divergence from the other species, suggesting that the taxon should be transferred to a different genus. A taxonomic update of the genus name is proposed through the validation of Passalites Gloger, 1841, with Passalitesnemorivagus (Cuvier, 1817) as the type species. Future research should focus on evaluating the potential existence of other species within the genus Passalites, as suggested in the literature.

Resurrection of the genus Subulo Smith, 1827 for the gray brocket deer, with designation of a neotype

The gray brocket deer, Mazama gouazoubiraG. Fischer, 1814, occurs in South America and presents an extensive degree of morphological and genetic variability. Previous phylogenetic research showed that the genus Mazama is polyphyletic and imposed the designation of a different genus-group name for M. gouazoubira. We aimed to review and clarify the taxonomy of M. gouazoubira through the proposal of updating the nomenclature for this taxon and by the characterization of specimens collected close to the original type locality (topotypes). The topotypes were characterized by morphological (general characterization and morphometry), cytogenetic (conventional staining, Ag-NOR, G- and C-banding, and fluorescence in situ hybridization), and phylogenetic (mitogenomes) approaches. We revealed chromosome homologies between cattle and M. gouazoubira using an entire set of cattle whole chromosome painting probes and propose an updated G-band idiogram for the species. The morphometric analysis did not discriminate the individuals of M. gouazoubira, including the topotypes, from other small brocket deer species. However, the phylogenetic analysis, based on a Bayesian inference tree of the mitogenomes, confirmed the polyphyly of the genus Mazama and supported the need to change the gray brocket deer genus-group name. Based on our revision, we validated the genus SubuloSmith, 1827, and fixed a type species for the genus. In the absence of the holotype, we denominated a neotype described by the collection of a male topotype in Paraguay. The nomenclature rearrangement presented here is a starting point that will assist in the taxonomic resolution of Neotropical deer.

Chromosomal Polymorphism and Speciation: The Case of the Genus Mazama (Cetartiodactyla; Cervidae)

Chromosomal polymorphism plays a major role in speciation processes in mammals with high rates of karyotypic evolution, as observed in the family Cervidae. One remarkable example is the genus Mazama that comprises wide inter- and intra-specific chromosomal variability. To evaluate the impact of chromosomal polymorphisms as reproductive barriers within the genus Mazama, inter-specific hybrids between Mazama gouazoubira and Mazama nemorivaga (MGO × MNE) and intra-specific hybrids between cytotypes of Mazama americana (MAM) differing by a tandem (TF) or centric fusion (Robertsonian translocations—RT) were evaluated. MGO × MNE hybrid fertility was evaluated by the seminal quality and testicular histology. MAM hybrids estimation of the meiotic segregation products was performed by sperm-FISH analysis. MGO × MNE hybrids analyses showed different degrees of fertility reduction, from severe subfertility to complete sterility. Regarding MAM, RT, and TF carriers showed a mean value for alternate segregation rate of 97.74%, and 67.23%, and adjacent segregation rate of 1.80%, and 29.07%, respectively. Our results suggested an efficient post-zygotic barrier represented by severe fertility reduction for MGO × MNE and MAM with heterozygous TF. Nevertheless, RT did not show a severe effect on the reproductive fitness in MAM. Our data support the validity of MGO and MNE as different species and reveals cryptic species within MAM.

Acoustic parameters of courtship and human-directed friendly vocalisations in seven species of Neotropical deer in captivity

Context Polygynous deer rut vocalisations have been found to be highly conspicuous, typical of the species and important in sexual selection. Information about vocalisations is not available for Neotropical species (subfamily Odocoileinae). Aims The objective was to record courtship vocalisations from all Neotropical deer available, looking for differences among species useful for taxonomic identification, characterise the vocalisations according to acoustic parameters and to try to determine functions. Methods Four species of brocket deer (red, Mazama americana (n = 9); grey, M. gouazoubira (n = 7); Amazonian brown, M. nemorivaga (n = 3); Brazilian dwarf, M. nana (n = 1)), and one individual each of marsh (Blastocerus dichotomus), white-tailed (Odocoileus virginianus) and taruca (Hippocamellus antisensis) deer were recorded in captivity at two institutions, in conditions of courtship or human interaction. The acoustic analysis was performed with Praat. Data from the first three species of Mazama were analysed statistically with a multilevel model with two layers. Key results In the context of courting either females or humans, male deer produced low-intensity, short-duration (0.1–0.3 s) bleats with fundamental frequencies (F0) between 100 and 400 Hz; calls were similar among species. The duration of these calls for Amazonian brown brocket males was significantly longer than for males of the other two species. Females of two species had longer-duration calls than did males, in friendly interactions with humans. F0 differences among species for both friendly and courtship calls were almost significant for males of M. gouazoubira. Individual differences were highly significant for both duration and mean F0. Mean F0 for courtship calls of adult males was not correlated with body size in six of the seven species, in contrast to the theory of acoustic allometry. Conclusions The production of male courtship bleats is probably a basic feature of Odocoiline deer and is probably important in sexual selection and female choice. The differences from one species to another are not sufficient for taxonomic use but may be incipient isolating mechanisms between grey and Amazonian brown brocket deer. Implications Studies of deer vocalisations have shown their importance in sexual selection and their incredible variety in closely related species and subspecies, but they have dealt mainly with Old World deer. This study fills a gap in our knowledge, as the first on Neotropical deer, which constitute six genera and 17 species and are widely distributed in the Americas. These data are important for future studies on the function and phylogeny of deer vocalisations.