Predictive distribution modelling of newly described endemic Dinaric species Cirsium greimleri Bureš

Cirsium (thistle) is one of the most taxonomically demanding genera within the Compositae. These taxonomic difficulties are hypothesized to result from limited morphological differentiation, incipient speciation and/or hybridization among taxa, and misinterpretations of faded and incomplete herbarium specimens. According to the latest data, the Dinarides and the Eastern Alps are inhabited by the endemic, diploid, newly described species Cirsium greimleri, which often occurs in sympatry with C. rivulare and C. erisithales. The area of the related, vicarious, tetraploid, and endemic species C. waldsteinii is limited to the southeastern Carpathians. Considering that the new knowledge refutes the existence of C. waldsteinii in Bosnia and Herzegovina, it was necessary to review all C. waldsteinii data discovered so far in Bosnia and Herzegovina. The results obtained from the distribution of the species, the predictive modelling of its ecological niche, and the analysis of the genome size confirmed the existence of the species C. greimleri in Bosnia and Herzegovina and its potential hybridization. This study indicates the need for further research into the sympatry of C. greimleri and its relatives, as well as the essential taxonomic revision of this complex.