Hybrid Origin of the Apogamous Fern Dryopteris hondoensis (Dryopteridaceae)

Abstract

We report that the triploid apogamous species Dryopteris hondoensis Koidz. shares its sequences with the D. erythrosora complex (D. erythrosora, D. caudipinna and D. koidzumiana) and D. chinensis at two nuclear markers (PgiC and GapCp). This is the first report of reticulate evolution between subg. Erythrovariae sect. Erythrovariae, to which D. erythrosora, D. caudipinna and D. koidzumiana and D. hondoensis belong, and sect. Aemulae of subg. Dryopteris, to which D. chinensis belongs. Apogamous species of Dryopteris may hybridize with distantly related species congeners.