Molecular data have provided many insights into cetacean evolution but some unsettled issues still remain. We estimated the topology and timing of cetacean evolutionary relationships using Bayesian and maximum likelihood analyses of complete mitochondrial genomes. In order to clarify the phylogenetic placement of Sotalia and Steno within the Delphinidae, we sequenced three new delphinid mitogenomes. Our analyses support three delphinid clades: one joining Steno and Sotalia (supporting the revised subfamily Stenoninae); another placing Sousa within the Delphininae; and a third, the Globicephalinae, which includes Globicephala, Feresa, Pseudorca, Peponocephala and Grampus. We also conclude that Orcinus does not belong in the Globicephalinae, but Orcaella may be part of that subfamily. Divergence dates were estimated using the relaxed molecular clock calibrated with fossil data. We hypothesise that the timing of separation of the marine and Amazonian Sotalia species (2.3 Ma) coincided with the establishment of the modern Amazon River basin.

Cactaceae Juss. is a family comprising 124 genera and about 1438 species which are distributed from Canada to Patagonia, with the largest diversity in tropical and subtropical America (see e.g., Hunt et al. 2006). The flora of Brazil include 39 Cactaceae genera and 261 species, of which 14 genera and 54 species can be found at Rio de Janeiro state, so showing its importance for the biodiversity of cacti (BFG 2015).

No abstract

Cactaceae Juss. is a family which comprises 124 genera and about 1438 species distributed from Canada to Patagonia, with the largest diversity in tropical and subtropical regions of Americas (see e.g., Hunt et al. 2006). The flora of Brazil includes 39 Cactaceae genera and 261 species, of which 14 genera and 54 species can be found the Rio de Janeiro state, highlighting the importance of this state to the biodiversity of Brazilian cacti (see BFG 2015). These species are highly affected by anthropic disturbances, which cause rapid habitat destruction, especially affecting the narrowly distributed endemic taxa, with 31% of the family being threatened, demonstrating the high anthropogenic pressures on the biodiversity in arid lands (Goettsch et al. 2015).

Arthrocereus grandiflorus sp. nov. is described on the basis of field surveys, macro- and micromorphological (pollen grains) data, and analysis of literature. The new species is endemic to the Brazilian Cerrado and its two subpopulations were found in the municipality of Diamantina, Minas Gerais State. Comments on its morphological affinities with related taxa, geographical distribution, phenology, habitat, conservation status, and original photographs of living specimens are provided. In terms of conservation, it was assessed according to IUCN criteria as Critically Endangered (CR).