The genusCyperusin the eastern Po Plain (Italy): historical and recent data

Abstract

AbstractThe genus Cyperus L. is revised in the eastern Po Plain and in the Po Delta (Veneto and Emilia-Romagna Regions, Italy), based on historical data analysis, examination of public herbaria and field observations. The genus includes autochthonous, long-time naturalized and recently introduced species: 16 taxa are recognized as actually present in the study area, whereas two others were recorded only once. Most species of the genus live along the course of the Po river, e.g. the recently identified Cyperus odoratus L., and/or in the rice fields. Some naturalized species of Cyperus are considered invasive, e.g. Cyperus esculentus L. and Cyperus glomeratus L.; others, e.g. Cyperus microiria Steud., Cyperus eragrostis Lam. and even C. odoratus, have recently been spreading widely. Cyperus glaber L., Cyperus strigosus L. and Cyperus erythrorhizos Muhl. are rare species. The latter was only recently detected for the first time in Europe and is here reported from two additional sites, the oldest dating back ...