Majority of crucifers (Brassicaceae) in the flora of Ukraine have bivalved (monomericarpous), bilocular, many- or few-seeded dehiscent siliques and silicles. A much smaller number of species has bisegmented (rostro-valvatus or bimericarpous) fruits (tribe Brassiceae). Very few species have indehiscent, bi- or unilocular (Clypeola, Euclidium, Goldbachia, Myagrum, Sobolewskia, Coronopus) or aseptate (Biscutella, 1 species) silicles. Species of only three genera (Calepina, Bunias and Neslia) are characteristic of the crumbling silicles, due to development of the dehiscent zone between the fruit and the pedicle. One additional separation zone is formed only in the fruits of Neslia paniculata, between the ger men and stylus. Rare features of the fruits are most characteristic for invasive taxa of the studied flora. Some morphological features deserve attention as structural novelties or as potential novelties, namely the following: presence of a ‘beak’ (distal segment); lack of septum in silicles; narrow, navicular valves (stenoseptate fruits); development of the separation zone between the fruit and pedicle, formation of two separation zones in one fruit (Neslia). We assume that unique features of the fruits demonstrate phenotypical manifestation of rare genetic mutations and probably therefore they are most typical for species of mono- or oligotypic tribes.
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