Sistemática e biogeografia do complexo automolus infuscatus (aves: furnariidae): testando hipóteses de diversificação para o neotrópico

Abstract

Abstract. Sistematics and Biogeography of the Automolus infuscatus complex (Aves:Furnariidae): Testing diversification hypotheses to the Neotropic. Recent revisions of the avian neotropical genus Automolus and the Furnariidae family pointed to the paraphyly of A. infuscatus and revealed a species complex comprising A. infuscatus, A.ochrolaemus, A. paraensis, A. leucophthalmus, A. lammi and A. subulatus, the latter historically classified in the genus Hyloctistes. The detailed knowledge of the taxonomy, geographic distribution, phylogenetic relationship and divergence times of a taxon allows to explore its evolutionary history and test different scenarios of diversification. Different biogeographical hipotheses were proposed to explain the patterns of distribution found in the neotropical lowland forests biota, where the species of the complex inhabit. These hypotheses, generally, relate lineages diversification to the geological evolution of the landscape and cycles of forestry expansion and retraction associated with climatic variations. In this context, we inferred the phylogenetic relationships, divergence times and biogeography of the A. infuscatus complex seeking to unveil the cryptic diversity within the complex and reveal its evolutionary history. To do that we sequenced two mitochondrial (ND2 and cytb) and three nuclear markers (G3PDH, ACO, Fib7) comprising 302 individuals belonging to all species in the complex and most described subspecies. Our analysis support the paraphyly of A. infuscatus, indicating the existing of at least two distinct clades not closely related. The remaining species were all recovered as monophyletic. Notwithstanding, a well structured intraspecific diversity was found with 19 lineages suggesting a great cryptic diversity within the described species. A. subulatus was recovered within the complex, corroborating its positioning inside the genus. The patterns of distribution encountered match with known distribution patterns of neotropical lowland birds. In spite of the high congruence between distributions of different lineages, with several sister lineages currently separated by the same barriers, the temporal incongruence between divergences of lineages co-separated by the same barriers reveals a complex evolutionary history. While older events might be related with the emergence of barriers such as the Andes and major amazonian rivers, younger events suggest dispersal after the consolidation of those barriers. Our analysis suggest that the complex had its origin around 6 million years (Ma) and inhabited Western Amazonia in Late Miocene-Early Pliocene. Considering the riparian habit of species in its sister clade, the rise and early diversifications of the complex may be related to the establishment of terra firme forests as it changed form a floodplain to a fluvial system.