Updated distribution of rare stonewort Chara kokeilii A.Braun (Charophyta) in Southeast Europe with environmental notes

A new site for stonewort Chara kokeilii A.Braun was recorded in a Mediterranean shallow lake Prološko Blato Retention, Croatia, SE Europe. The species was associated with the vegetation alliance Potamogetonion graminei Westhoff & Den Held. This record has been compared with four other sites (Albania, Bulgaria, Greece and Montenegro) from which the species was recorded in SE Europe, regarding the species morphological traits, environmental parameters and vegetation types. It is possible that the main distribution area of this species is in Southeast Europe, a statement that is supported by previous micropaleontological research. This research provides new data on distribution and ecological affiliation of the critically endangered C. kokeilii (IUCN Red List Categories and Criteria).