Phylogeny and evolution of the neotropical species of Pteris (Pteridaceae)

Abstract

Pteris (Pteridaceae) is a genus of ferns with a great diversity of species (ca. 250), pantropical, an ideal group for addressing research on diversification, biogeography, hybridization and polyploidy, which that have long been understudied in ferns. In this project will be carried out the phylogenetic and evolutionary study of the Neotropical species of the genus Pteris. This is part of a larger study, in collaboration with Asian, African and American researchers that aims to review the classification of Pteris, as well as other groups in Pteridaceae. Of the total of species in the genus, in Tropical America occurs about 55 species of which 24 occur in Brazil. Most of the Brazilian species occurs a long the Atlantic Forest and six are endemics. This study will be based on sequencing of three plastidial molecular markers (atpA, chlL, and rbcL) and also on the analyses of morphologic data. Intends to conduct field work to collect samples on silica gel of some representatives of the genus and related groups which constitute part of the internal and external groups for our analyses, borrow materials to Brazilian and foreign herbaria, which not will be visited. The main objectives of this study are to test if the neotropical species of Pteris, restricted to Atlantic Forest, form a monophyletic group; identify the neotropical major evolutionary lineages of Pteris; analyze the evolution of morphological characters, optimizing them on cladograms obtained in our the phylogenetic analysis; study the phylogenetic relationships among Neotropical species of Pteris with African and Asian species; investigate questions about the origin of the group and historical biogeography, i.e., to know what is the ancestral area for the group and estimate the time of divergence between the lineages, and compare these estimates with paleogeographic historical events described for the neotropical region that may have influenced the diversification of neotropical Pteris. (AU)