Carex ×kneuckeri, a hybrid new for central Europe and neotypification of this name

Abstract

Carex ×kneuckeri (C. hirta × C. rostrata) is reported here for the first time to occur in south-eastern Poland and central Europe. Although both parents are widespread and common species in Europe, the hybrid is extremely rare or overlooked, worldwide only known from France (one locality), Sweden (two localities) and now also Poland (one locality). Carex ×kneuckeri has the general appearance of C. rostrata, but has hairy utricles and hairy leaf sheaths, like C. hirta. Phylogenetic analysis of plastid matK and (cloned) nuclear ribosomal ITS sequences indicates a close relationship of C. ×kneuckeri with C. rostrata. The ITS alignment shows complex mutational patterns and a clear dominance of the C. rostrata sequence type, but also an indication of the presence of the C. hirta sequence type. As no original material of C. ×kneuckeri could be traced, a specimen from the Swedish Museum of Natural History (S) is chosen here as the neotype for this name.