Atlas Florae Europaeae notes, 33. Taxonomic synopsis of East European species of the Cytisus ratisbonensis group (Fabaceae)

A group of species of Cytisus sect. Tubocytisus with strictly lateral inflorescences, commonly referred to as C. ratisbonensis s.l., is critically revised in Eastern Europe on the basis of morphology and comprehensive treatment of herbarium specimens and observations. Seven species and two presumed hybrids are recognised. Complete accounts are provided for each species, with synonyms, typifications, brief morphological descriptions, data on ecology and distributions, taxonomic and nomenclatural annotations. Cytisus polonicus is described as new to science, separated from C. ratisbonensis on the basis of morphology and diploid (vs. tetraploid) chromosome count. The lectotype of C. elongatus is superseded and a new lectotype is designated; this name has priority for the species previously known as C. triflorus . Six species names are newly placed to the synonymy: Chamaecytisus pineticola under Cytisus ruthenicus s. str., and Cytisus czerniaevii , C. leucotrichus , C. lindemannii , C. ponomarjovii and Chamaecytisus korabensis under Cytisus elongatus . The presumed hybrid between C. ruthenicus and C. elongatus , which was incorrectly known as C. czerniaevii , is described here as C. semerenkoanus . Cytisus lithuanicus , which has been an obscure name since its original publication, is resurrected for a newly-recognised octoploid species, which is endemic to eastern Poland, western Belarus and north-western Ukraine. The name C. cinereus is re-instated for the species previously known as C. paczoskii , and C. horniflorus is added to its synonymy; its complete distribution area is circumscribed, and its occurrence in Austria, Poland, Romania, Serbia and Slovakia is documented. Cytisus kreczetoviczii and C. elongatus are reported for the first time from Belarus, and the latter species also from Bosnia and Herzegovina, Montenegro and Slovenia. Cytisus borysthenicus and C. elongatus are reported as new to some territories in European Russia. Cytisus ratisbonensis s. str. is treated as absent from Eastern Europe. The ...