This article shows some contributions to the knowledge of the genus Carex (Cyperaceae) in the Iberian Peninsula. Among them we highlight the confirmation of C. pseudobrizoides Clavaud for the Iberian Peninsula (Basque Country). The results of the morphological study carried out to differentiate this species from the closely related C. brizoides L., also present in the territory, are showed. A map of the Iberian distribution of C. praecox Schreb. is provided. C. umbrosa is cited for the first time for the Iberian System, the presence of C. montana L. in this mountain system is rejected, the distribution area of C. riparia in Eastern Andalusia is discussed, and a new chromosome number for C. olbiensis Jord. is reporte
