Spatial analysis and distribution modeling of Aconitum moldavicum in Ukrainian Carpathians and adjacent territories with special reference to the algorithm used

The paper aimed to conduct a comprehensive analysis of all available sources (including herbarium vouchers, publications, and datasets) on the exact distribution of Aconitum moldavicum in the Ukrainian Carpathians to build the maps modeling the species distribution in this region and adjacent territories.
Aconitum moldavicum is a Pancarpathian subendemic distributed widely along the Carpathian Mountain range and scattered out to some of the adjacent lowland territories. Surprisingly, A. moldavicum was found to be quite rare for the Transcarpathian Lowland, where it is represented only by A. moldavicum subsp. hosteanum. Just near the border with Slovakia, A. moldavicum subsp. moldavicum occurs in the Vygorlat Mts., while along with all other parts of the Vygorlat-Gutyn Carpathians it does not appear. However, both taxa, A. moldavicum subsp. moldavicum and A. moldavicum subsp. hosteanum, quite frequently appear in the Ciscarpathia and Volhynia-Podilia Highland together with their hybrid A. moldavicum nothosubsp. confusum.
Aconitum moldavicum nothosubsp. porcii and nothosubsp. simonkaianum occur exclusively in the Marmarosh region of the Ukrainian Carpathians, and probably A. moldavicum nothosubsp. porcii can also be re-find in the Chornohora. Presence of A. moldavicum nothosubsp. simonkaianum in the Volhynia-Podilia Highland seems to be doubtful because there are no other pieces of evidence despite the only voucher hosted at GJO herbarium. Moreover, other vouchers collected by B. Błocki from the same region were identified as belonging to A. moldavicum nothosubsp. hosteanum.
We used different algorithms of SDM (MaXent, BioClim, GARP, EnvDist, TIN, and IDW) to check the most sufficient and most closely representing a real distribution of A. moldavicum in the area studied. BioClim correctly pointed to the geographic centers of the species in the Carpathians, Volhynia-Podilia Highland, and in Polish Uplands. Traditionally applied algorithm MaxEnt underestimates the probability of occurrence of species in the area of confirmed presence and, at the same time, overestimates it in the area beyond the known extent of species occurrence. IDW algorithm showed similar results with MaxEnt and confirmed its potential suitability for SDM purposes.