Phylogeography of the cactophilic species Drosophila gouveai: demographic events and divergence timing in dry vegetation enclaves in eastern Brazil

Abstract

Aim The aim of this study was to assess the causal mechanisms underlying populational subdivision in Drosophila gouveai, a cactophilic species associated with xeric vegetation enclaves in eastern Brazil. A secondary aim was to investigate the genetic effects of Pleistocene climatic fluctuations on these environments. Location Dry vegetation enclaves within the limits of the Cerrado domain in eastern Brazil. Methods We determined the mitochondrial DNA haplotypes of 55 individuals (representing 12 populations) based on sequence data of a 483‐bp fragment from the cytochrome c oxidase subunit II (COII) gene. Phylogenetic and coalescent analyses were used to test for the occurrence of demographic events and to infer the time of divergence amongst genetically independent groups. Results Our analyses revealed the existence of two divergent subclades (G1 and G2) plus an introgressed clade restricted to the southernmost range of D. gouveai. Subclades G1 and G2 displayed genetic footprints of range expansion and segregated geographical distributions in south‐eastern and some central highland regions, east and west of the Paraná River valley. Molecular dating indicated that the main demographic and diversification events occurred in the late to middle Pleistocene. Main conclusions The phylogeographical and genetic patterns observed for D. gouveai in this study are consistent with changes in the distribution of dry vegetation in eastern Brazil. All of the estimates obtained by molecular dating indicate that range expansion and isolation pre‐dated the Last Glacial Maximum, occurring during the late to middle Pleistocene, and were probably triggered by climatic changes during the Pleistocene. The current patchy geographical distribution and population subdivision in D. gouveai is apparently closely linked to these past events.

Model-based analysis supports interglacial refugia over long-dispersal events in the diversification of two South American cactus species

“…Importantly, these estimates were similar to those obtained from two cpDNA and one nuclear gene (Bonatelli et al, 2014), supporting that the splitting times for the most ancient lineages in the two species took place primarily during the early Pleistocene whereas the derived lineages diversified in a period within the early and middle Pleistocene. These estimates fell within a period characterized by range shifts in dry vegetation (Prado and Gibbs, 1993;Pennington et al, 2004) and also recognized as an age of speciation and intraspecific differentiation of other species associated with the open and xeric environments in eastern Brazil, such as the rodent species of the genus Calomys (Almeida et al, 2007) and some cactophilic drosophilids of the D. buzatti cluster (Moraes et al, 2009;Franco and Manfrin, 2013).…”

“…This is not true for species occurring in xeric and open environments as the rocky savanna habitats in Eastern South America, which show more idiosyncratic patterns (Turchetto-Zolet et al, 2013). For instance, distinct responses have been found in species distribution ranges during the same paleoclimatic phases such as signals of expansion in the Drosophila buzatti cluster, which exclusively uses decaying stems of cactus as breeding sites (Moraes et al, 2009), shrink in a tree species of Cerrado (savanna) biome, Dipteryx alata Vogel (Collevatti et al, 2013) and stability in the Neotropical coastal species of orchid Epidendrum fulgens (Pinheiro et al, 2011), and in the gecko Phyllopezus pollicaris, a specialist species of rocky outcrop habitats (Werneck et al, 2012).…”

Out of the deep: Cryptic speciation in a Neotropical gecko (Squamata, Phyllodactylidae) revealed by species delimitation methods

“…Resulting species tree Posterior probabilities of full model Bayesian and ML (Phy,((MaC,(DarA,DarB)), ((Ma,Gec), (A,(B,((C,D),(E,(F,(G,H))))))))) 0.963-0.982 * Beast (Phy, (MaC,((Ma,Gec), (A,((C,D),((E,B),(G,(F,H)))))))) 0.891-0.914 et al, 2006) and SDTF endemic Drosophila species (Franco and Manfrin, 2013;Moraes et al, 2009). However, recent studies point towards ancient events of lineage diversification for Cerrado vertebrates, dating back to the Neogene (Giugliano et al, 2013;Prado et al, 2012;Werneck et al, 2012).…”

“…The evolution of groups sharing a Caatinga-Cerrado distribution remains a poorly understood subject in South American biogeography (Werneck, 2011) and few studies have implemented molecular techniques to investigate the relationship between those biomes (Almeida et al, 2007;Faria et al, 2013;Moraes et al, 2009;Recoder et al, 2014;Werneck et al, 2012). Dissimilarities noted between G. amarali and G. geckoides include ecological differences such as clutch and egg sizes (Colli et al, 2003), karyological differences in chromosome number and type (Pellegrino et al, 2009), and morphological differences in pholidosis and coloration patterns (Cassimiro and Rodrigues, 2009;Vanzolini, 1953Vanzolini, , 2005.…”

Filogenia do Complexo Drosophila Buzzatii (Grupo Repleta): Inferências de Análises Multilocus Mitocondriais e Nucleares.

“…3-Eventos demográficos de expansão populacional e os processos de diferenciação dentro do cluster podem estar relacionados a eventos não sincrônicos de expansão e retração da vegetação xerófita na América do Sul, durante alterações climáticas causadas por eventos paleoclimáticos (Ab' Saber, 1977;Sene et al 1988;de Brito et al 2002a;Moraes et al 2009). …”