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Cytotoxicity-guided fractionation of the MeOH extract of Helleborus lividus Aiton ex Curtis (Ranunculaceae) resulted in the isolation of five undescribed bufadienolide glycosides and two undescribed bufadienolides, along with three known compounds. Their structures were determined by detailed spectroscopic analysis and hydrolysis studies. The isolated compounds showed cytotoxicity against HL-60 human leukemia cells and A549 human lung adenocarcinoma cells, with IC50 values ranging from 2.20 ± 0.01 nM to 0.77 ± 0.01 μM. The undescribed compound 3β-[(O-β- d -glucopyranosyl-(1 → 4)-α- l -rhamnopyranosyl)oxy]-14β,16β-dihydroxy-5β-bufa-20,22-dienolide induced apoptosis in HL-60 cells via a mitochondria-dependent apoptotic pathway. The average IC50 values of bufadienolide monorhamnosides for HL-60 and A549 cells were 10–20 times lower than those for Na+/K+ ATPase, implying that they induce tumor cell death via a mechanism of action other than Na+/K+ ATPase inhibition.

For two years (2006 − 2007), seedlings and young plants of Helleborus lividus Aiton were grown in containers with a peat substrate, which was deacidified with calcium carbonate at the following doses: 2.5, 5.0, 7.5 and 10.0 g dm-3. The plants were divided into two groups in each variant of CaCO3 dosage, one fertilized with a solution of a lower (0.1%) and the other with a higher (0.3%) concentration of Peters Professional PL Special (15:11:29). Helleborus lividus growth in the first year of cultivation depended on the calcium carbonate dose. Taller plants, with a higher number of leaves, were produced using calcium carbonate at a dose of CaCO3 2.5-5.0 g dm-3. In the second year of cultivation good quality plants - taller, with higher numbers of leaves and shoots, were produced when grown in a substrate with 2.5-7.5 g CaCO3 per dm3. The application of solutions of various concentrations in top dressing did not have an effect on the growth of Helleborus lividus in the first year of cultivation, while in the second year taller plants, with more leaves as well as flowers and buds, were produced when applying a 0.3% fertilizer solution.

Mitotic chromosome numbers are reported from 35 vascular plant taxa endemic to the Balearic Islands that are poorly known cytogenetically. The chromosome numbers of Chaenorhinum rodriguezii (2n = 14), Coristospermum huteri (2n = 22), Carduus ibicensis (2n = 26), Filago petro-ianii (2n = 26), Ononis crispa ssp. zschackei (2n = 30), and Ophrys bertolonii ssp. balearica (2n = 36) were determined for the first time. New chromosome numbers are reported in Pimpinella bicknellii (2n = 22), Calamintha rouyana (2n = 46), Vicia bifoliolata (2n = 14), and Teucrium asiaticum (2n = 30). A new diploid cytotype (2n = 16) was found in Ranunculus paludosus ssp. barceloi, which is restricted to populations from the western Balearics (Eivissa and Formentera), whereas tetraploid plants are known from the eastern Balearics (Mallorca). It is suggested that the tetraploid cytotype arose from the diploid cytotype through autopolyploidy. The idiograms of Coristospermum huteri, Pastinaca lucida, Pimpinella bicknellii, Carduus ibicensis, Helianthemum scopulicolum, Helichrysum crassifolium, Vicia bifoliolata, paeonia cambessedesii, Helleborus lividus, Ranunculus paludosus ssp. barceloi, and Linaria aeruginea ssp. pruinosa are determined for the first time. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 153, 463–476.

Helleborus argutifolius was proposed as a species distinct from H. lividus Aiton (1789) by Viviani in 1824. Some authors have treated it at subspecific rank, but only now is a subspecific epithet validly published in combination with the earliest available specific name. A new combination is also made at (notho-)subspecific rank for hybrids between representatives of the two taxa. The remarkable discrepancy between H. lividus Aiton in Curtis (Jan. 1789) and H. lividus sensu Aiton, Hort. Kew. (Aug./Sept. 1789) is traced to an unacknowledged change of concept between the 6th and 7th editions of Miller's Gardeners Dictionary (1752, 1759). The nomenclatural status of the names applied to these plants by Schiffner (1889, 1890) and other authors is analysed.