The mid-Cretaceous is a period of sudden turnover from gymnosperm to angiosperm-dominated floras. The aim was to investigate the fossil plant ecology in order to follow the spread of angiosperm taxa.Floristic lists and localities from the latest Albian-Cenomanian of Europe are analysed with Wagner's Parsimony Method, a clustering method currently used in phylogeny (cladistics).Wagner's Parsimony Method points out that (a) gymnosperms dominated brackish water-related environments while angiosperms dominated freshwater-related environments (e.g. swamps, floodplains, levees, channels), (b) angiosperms showed the highest diversity in stable, freshwater-related environments, (c) a single angiosperm, 'Diospyros' cretacea, is restricted to brackish water-related environments and (d) the families Lauraceae and Platanaceae were exclusive to disturbed, braided river environments, implying a opportunist strategy for early tree angiosperms.During the Mid-Cretaceous, European floras were characterized by (a) coastal gymnosperms, (b) highly diversified fluvial angiosperms and (c) the first European brackish water-related angiosperm.