Effects of past climate onPassiflora actinia(Passifloraceae) populations and insights into future species management in the Brazilian Atlantic forest

Abstract

The Brazilian Atlantic Rainforest is one of the most diverse and threatened ecoregions on the planet and displays high levels of endemism. Despite several population analyses and phylogeographical studies, the origins of its species richness and the evolutionary processes that gave rise to this diversification remain poorly understood, especially at the southern edge of the Atlantic Forest. Passiflora actinia is an indigenous species from the southern Atlantic Forest and, as such, was influenced by climatic changes during the Pleistocene. In this study, we investigated the effects of past climate changes on the genetic diversity of P. actinia, using nuclear and plastid markers. We subsequently suggest strategies for the preservation of this species in particular and the whole ecoregion in general. We employed phylogeographical methods and combined these results with past, present and future ensemble niche models. Genetic variability in P. actinia was similar to that of other species with similar geographical distributions, and geographical structuring was not observed based on either type of genetic marker. Diversification in P. actinia was dated to the Pleistocene, suggesting that climate changes could have influenced the distribution of genetic diversity in this species. Our results predicted that suitable P. actinia habitat will persist in the highlands but will be reduced in the lowlands, especially with higher greenhouse gas concentrations. Conservation efforts should focus on populations with unique genetic units and populations from areas with greater climatic instability. Habitat loss due to deforestation in the Atlantic Forest constitutes a major risk to this species, especially to small populations or those with low diversity indices.

Mapping the habitat suitability of Andira humilis Mart. ex Benth. (Fabaceae) as a means to detect its associated galling species in Brazil

“…The annual mean temperature seems to be the main biologically important variable, shaping the distribution of several species in the Neotropical region. Similar to our study, annual mean temperature was the variable that contributed most to the ecological model of Passiflora actinia Hook (Passifloraceae) from the southern Atlantic Forest (Teixeira, Mäder, Arias, Bonatto, & Freitas, 2016).…”

Phylogeographic Studies Depict the Role of Space and Time Scales of Plant Speciation in a Highly Diverse Neotropical Region

“…The different demographic signatures of northern and southern populations suggest regions in which the forest was fragmented (in the southern populations) and continuous (in the northern populations) during the Last Glacial Maximum (LGM), following the pattern expected for glacial refuges (Bennett and Provan, 2008). The same pattern has been reported for other plant species, including a tree species, Dalbergia nigra (Ribeiro et al, 2011) and a liana, Passiflora actinia (Teixeira et al, 2016). Contrasting results were provided by Pinheiro et al (2011) using an herbaceous orchid species that occurs in sand dune vegetation close to the seashore.…”

Multiple markers, niche modelling, and bioregions analyses to evaluate the genetic diversity of a plant species complex

“…The plant migrations triggered by the Quaternary climate oscillations, combined with the non-uniform landscape composition, may have contributed to the diversification of the evolutionary lineages of the P. integrifolia complex. This dynamic also underlies the diversification and range expansion of other Petunia species [ 21 ] and of the genus as a whole [ 24 ], and mirrors that of other plant species from the same region [ 31 , 102 , 103 ], in line with the theory of Andean components in the southern Brazilian flora [ 104 ]. The differentiation between habitats and the stability found in niche modelling analysis reinforce the idea that there are four genetic lineages: P. integrifolia , P. depauperata , P. bajeensis, and P. inflata + P. interior .…”