Wolfgang Wetschnig

Inferences of biogeographical histories within subfamily Hyacinthoideae using S-DIVA and Bayesian binary MCMC analysis implemented in RASP (Reconstruct Ancestral State in Phylogenies)

BACKGROUND AND AIMS Subfamily Hyacinthoideae (Hyacinthaceae) comprises more than 400 species. Members are distributed in sub-Saharan Africa, Madagascar, India, eastern Asia, the Mediterranean region and Eurasia. Hyacinthoideae, like many other plant lineages, show disjunct distribution patterns. The aim of this study was to reconstruct the biogeographical history of Hyacinthoideae based on phylogenetic analyses, to find the possible ancestral range of Hyacinthoideae and to identify factors responsible for the current disjunct distribution pattern. METHODS Parsimony and Bayesian approaches were applied to obtain phylogenetic trees, based on sequences of the trnL-F region. Biogeographical inferences were obtained by applying statistical dispersal-vicariance analysis (S-DIVA) and Bayesian binary MCMC (BBM) analysis implemented in RASP (Reconstruct Ancestral State in Phylogenies). KEY RESULTS S-DIVA and BBM analyses suggest that the Hyacinthoideae clade seem to have originated in sub-Saharan Africa. Dispersal and vicariance played vital roles in creating the disjunct distribution pattern. Results also suggest an early dispersal to the Mediterranean region, and thus the northward route (from sub-Saharan Africa to Mediterranean) of dispersal is plausible for members of subfamily Hyacinthoideae. CONCLUSIONS Biogeographical analyses reveal that subfamily Hyacinthoideae has originated in sub-Saharan Africa. S-DIVA indicates an early dispersal event to the Mediterranean region followed by a vicariance event, which resulted in Hyacintheae and Massonieae tribes. By contrast, BBM analysis favours dispersal to the Mediterranean region, eastern Asia and Europe. Biogeographical analysis suggests that sub-Saharan Africa and the Mediterranean region have played vital roles as centres of diversification and radiation within subfamily Hyacinthoideae. In this bimodal distribution pattern, sub-Saharan Africa is the primary centre of diversity and the Mediterranean region is the secondary centre of diversity. Sub-Saharan Africa was the source area for radiation toward Madagascar, the Mediterranean region and India. Radiations occurred from the Mediterranean region to eastern Asia, Europe, western Asia and India.

The Scilla plumbea Puzzle-Present Status of the Genus Scilla Sensu Lato in Southern Africa and Description of Spetaea lachenaliiflora, a New Genus and Species of Massonieae (Hyacinthaceae)

We have studied a taxon from South Africa that has been hidden for more than 150 years within Scilla plumbea (Hyacinthaceae). However, phylogenetic reconstruction based on trnL-F data, morphological evidence (including seed characters), and karyology suggest independent status. DNA data place it close to the Daubenya alliance but not close to any particular genus of Massonieae previously included within Scilla s.l. Unique characters of seeds indicate that this taxon does not belong to the Daubenyaclade. Analysis of the iconotype of Scilla plumbea Lindl., on the other hand, reveals morphological details suggesting membership in the Scilla natalensis clade (= genus Merwillain the recent classification of Speta). Merwilla, however, occupies a basal position among Massonieae and is not related to the Daubenyaclade. Based on all data, we describe this taxon as a new genus and species Spetaea lacheneliifloraWetschnig & Pfosser.

Out of Africa: Miocene Dispersal, Vicariance, and Extinction within Hyacinthaceae Subfamily Urgineoideae

Disjunct distribution patterns in plant lineages are usually explained according to three hypotheses: vicariance, geodispersal, and long-distance dispersal. The role of these hypotheses is tested in Urgineoideae (Hyacinthaceae), a subfamily disjunctly distributed in Africa, Madagascar, India, and the Mediterranean region. The potential ancestral range, dispersal routes, and factors responsible for the current distribution in Urgineoideae are investigated using divergence time estimations. Urgineoideae originated in Southern Africa approximately 48.9 Mya. Two independent dispersal events in the Western Mediterranean region possibly occurred during Early Oligocene and Miocene (29.9-8.5 Mya) via Eastern and Northwestern Africa. A dispersal from Northwestern Africa to India could have occurred between 16.3 and 7.6 Mya. Vicariance and extinction events occurred approximately 21.6 Mya. Colonization of Madagascar occurred between 30.6 and 16.6 Mya, after a single transoceanic dispersal event from Southern Africa. The current disjunct distributions of Urgineoideae are not satisfactorily explained by Gondwana fragmentation or dispersal via boreotropical forests, due to the younger divergence time estimates. The flattened winged seeds of Urgineoideae could have played an important role in long-distance dispersal by strong winds and big storms, whereas geodispersal could have also occurred from Southern Africa to Asia and the Mediterranean region via the so-called arid and high-altitude corridors.

Nicipe rosulata (Ornithogaloideae, Hyacinthaceae), a New Species from the Little Karoo in South Africa, with a New Combination in the Genus

Abstract A new species of Nicipe from the Little Karoo in South Africa is here described. Nicipe rosulata sp. nov. is characterized by its (3-)5-8 short and broad, somewhat leathery leaves disposed in a basal rosette, its narrowly ovate, acute-apiculate capsules, and its long papillate-echinulate seeds. This species is at first sight related to Nicipe britteniae and Ornithogalum lithopsoides based on their short leaves with ciliate to fimbriate margins, but it differs in floral and vegetative characters that clearly support its recognition as a distinct species. Nicipe britteniae differs from N. rosulata by the hard, distichous, ensiform, conduplicate, and densely fimbriate leaves and the rugose seeds. Ornithogalum lithopsoides clearly differs by the more numerous and much thinner leaves, and the rugose seeds, among other characters. Here we provide a detailed morphological description for Nicipe rosulata, including ecological and chorological data, and discuss relationships with its close allies. Finally, the recently described Ornithogalum lithopsoides, also from the Little Karoo, clearly belongs to Nicipe based on the leathery rosulate leaves all arising nearly at the same level, the relatively small flowers, the tepals with a dark longitudinal band mostly visible on the abaxial side, and the small capsules and seeds. This new combination in the latter genus is also presented here.

Phytochemical Investigations of Three Rhodocodon (Hyacinthaceae Sensu APG II) Species

The genus Rhodocodon (Hyacinthaceae sensu APG II) is endemic to Madagascar, and its phytochemistry has not been described previously. The phytochemistry of three species in this genus has been investigated, and eight compounds, including three bufadienolides (compounds 1, 4, and 5), a norlignan (2), and four homoisoflavonoids (compounds 3 and 6-8), have been isolated and identified. Compounds 1-3 and 6-8 have not been described previously. The COX-2 inhibitory activity of compound 6 and compound 7 acetate (compound 7A) was investigated on isolated colorectal cancer cells. Compounds 6 and 7A inhibited COX-2 by 10% and 8%, respectively, at a concentration of 12.5 μM compared to 12% for 1 mM aspirin (the positive control).