Home at last: the enigmatic genera Eriachaenium and Adenocaulon (Compositae, Mutisioideae, Mutisieae, Adenocaulinae)

The genera Eriachaenium and Adenocaulon (Compositae) have distinct but complex histories and both have been placed in a number of tribes across the family. For the first time the two genera are included in a molecular study and the results show that they are best placed in the tribe Mutisieae s.s. and are the only genera in the re-instated subtribe Adenocaulinae. When described, this subtribe contained only Adenocaulon and was found in the Inuleae. The study also confirms one of the conclusions of a recent morphological study that Eriachaenium and Adenocaulon are sister taxa. Past difficulties in tribal assignment are attributed to the distinct and unusual morphology of each genus. Both genera and the subtribe are described and a key to separate the genera is provided.Facultad de Ciencias Naturales y Muse

Home at last: the enigmatic genera Eriachaenium and Adenocaulon (Compositae, Mutisioideae, Mutisieae, Adenocaulinae)

The genera Eriachaenium and Adenocaulon (Compositae) have distinct but complex histories and both have been placed in a number of tribes across the family. For the first time the two genera are included in a molecular study and the results show that they are best placed in the tribe Mutisieae s.s. and are the only genera in the re-instated subtribe Adenocaulinae. When described, this subtribe contained only Adenocaulon and was found in the Inuleae. The study also confirms one of the conclusions of a recent morphological study that Eriachaenium and Adenocaulon are sister taxa. Past difficulties in tribal assignment are attributed to the distinct and unusual morphology of each genus. Both genera and the subtribe are described and a key to separate the genera is provided.Facultad de Ciencias Naturales y Muse

Mesozoic remagnetization of Upper Devonian carbonates from the Česis and Skaistgirys quarries (Baltic states)

The palaeomagnetic properties of Frasnian and Famennian dolomites from two quarries in Latvia and Lithuania respectively are compared. Famennian dolomites from Skaistgirys quarry (N Lithuania) revealed the presence of one distinct normal polarity component (D =14 degrees Celsius, I = 53 degrees Celsius, 95 = 4.2 degrees Celsius, n = 28 specimens). The reversed polarity component predominates in Frasnian dolomites from Česis quarry (Central Latvia). Only one hand specimen from this locality contained a component with the opposite direction. The mean direction from Česis quarry (D = 198 degrees Celsius, I = -53 degrees Celsius, 95 = 4.4 degrees Celsius, n = 22 specimens) is very close to that from Skaistgirys quarry and therefore was recorded most probably during the same event of remagnetisation but at a later stage. The remagnetizations of these dolomites were caused most probably by progressive oxidation of ferric sulphides to magnetite and finaly to hematite. A comparison of the palaeomagnetic poles obtained with the stable European APWP (Apparent Polar Wander Path) indicates a Late Jurassic/Early Cretaceous age for the remagnetization event. This estimation can be useful for chronostratigraphic linking of post-Palaeozoic tectonic activity and diagenetic events, so far very poorly recognized in this part of the European plate. Our data shows also that the Late Jurassic/Early Cretaceous part of the stable European APWP may still be inaccurate

Redundancy or progress? A response to Driscoll et al. (2019)

Driscoll et al. (Journal of Biogeography, 2019, 46, 2850–2859) provide a critique of ‘Countryside Biogeography’, but also include ‘Conservation Biogeography’ and ‘Agriculture Biogeography’ in their criticisms. Their main thesis is that these new sub-disciplines offer a ‘conceptual wrapper’ rather than distinctive frameworks and that the consequent redundancy of terms has the potential to sow confusion among biogeographers and slow progress. Here we argue that, far from sowing confusion Conservation Biogeography, for example, has provided important focal points for emerging scientific discourse, promoting new research, spawning undergraduate and graduate courses, and facilitating the formation of new scientific collaborations. The success or failure of a new sub-discipline depends on its utility. If new framings sow confusion, introduce redundancy and provide no new insights they will not be widely adopted and cited. The development of new sub-disciplines is a strong indicator of a vibrant, socially relevant and intellectually adventurous research area.Fil: Katinas, Liliana. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División de Plantas Vasculares; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Ladle, Richard J.. Universidade Federal de Alagoas; Brasi

New Late Vendian palaeogeography of Baltica and the TESZ

New palaeomagnetic poles obtained from the Vendian tuffs and basalts of western Ukraine indicate the necessity of a substantial revision of the Late Vendian-Early Cambrian palaeogeography of the Baltic plate. The palaeopole calculated for the most stable component isolated from the Vendian tuffs and basalts is far away from the Vendian-Cambrian apparent polar wander path (APWP), constructed on the basis of Scandinavian poles but is very close to the pole recently isolated from the Vendian sediments of the White Sea Region. Depending on the polarity of the newly-determined Late Vendian pole, two palaeogeographic models of the Baltic plate in the Late Vendian-Early Cambrian are possible. In our preferred model the Baltic plate moved at that time from the moderate southern latitudes to the equator rotating anticlockwise of ca. 120 degrees Celsius. This reconstruction explains the geological structures of the marginal zones of Baltica better than the previously proposed stationary model of the Late Vendian-Cambrian Baltica. According to the new late Vendian palaeogeographic scenario, the European, passive margin of Baltica was separated from an active, Avalonian margin of Gondwana. The Late Neoproterozoic tectonic structures of the Brunovistulian Terrane and the Małopolska Block were developed near the present day southwestern corner of Baltica that was tectonically active at that time. Alternative reconstruction shows the Baltic platemoving from the moderate northern latitudes in the Vendian, crossing palaeoequator in the latest Vendian, and reaching moderate southern palaeolatitudes in the Late Cambrian. This model, however, would have required exceptionally high plate velocity (ca. 33 cm/year)