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11. In situ pollen of voltzialean conifers from the Middle Triassic in Central Europe

Author

IVAU: Instituut voor Aardwetenschappen Utrecht, Marine palynology and palaeoceanography, Nowak, Hendrik, Kustatscher, Evelyn, Roghi, Guido, van Konijnenburg - van Cittert, Johanna H.A., IVAU: Instituut voor Aardwetenschappen Utrecht, Marine palynology and palaeoceanography, Nowak, Hendrik, Kustatscher, Evelyn, Roghi, Guido, and van Konijnenburg - van Cittert, Johanna H.A.

Published
2024

19. Conifer Cone and Dwarf Shoot Diversity in the Anisian (Middle Triassic) of Kühwiesenkopf/Monte Prà della Vacca (Dolomites, Northeastern Italy)

Author

Forte, Giuseppa, Kustatscher, Evelyn, Nowak, Hendrik, van Konijnenburg-van Cittert, Johanna H.A., Marine palynology and palaeoceanography, Marine Palynology, Marine palynology and palaeoceanography, and Marine Palynology

Subjects
fertile organs, amber, polliniferous cones, in situ pollen, Plant Science, seed cones, Ecology, Evolution, Behavior and Systematics
Abstract

Premise of research. The diversity of conifers from Kühwiesenkopf/Monte Prà della Vacca has been inferred previously on the basis of foliate branches/shoots and epidermal morphology. In this article we provide the description of the reproductive organs, which reveal a variety of forms, new morphologies and new taxa, and a comparison with other Permian–Triassic taxa, improving the knowledge of Triassic conifers. Methodology. The macromorphology, cuticles, and in situ pollen of the reproductive organs are described, and the macromorphological features are compared with those of other Permian–Triassic taxa. Pivotal results. The macro- and micromorphological analyses of the conifer reproductive organs of Kühwiesenkopf/Monte Prà della Vacca allow us to emend previously known taxa (i.e., Voltzia heterophylla, V. walchiaeformis, V. recubariensis, Pseudovoltzia edithae) and to describe new ones (i.e., cf. Voltzia sp. 1, Sidashia tridentata), providing in some cases almost complete whole-plant reconstructions. The macromorphological comparison of the Kühwiesenkopf/Monte Prà della Vacca taxa with other Permian–Triassic ones highlights the transitional character of some of them, especially P. edithae. The finding of amber anatomically connected to a V. walchiaeformis seed cone evidences the diversity of the botanical origins of the Anisian amber. Conclusions. The reproductive organs of the conifers of Kühwiesenkopf/Monte Prà della Vacca show in their morphology a mixture of characters typical of the early Permian to the Late Triassic Voltziales. Their study improves our knowledge of the reproductive biology of Anisian conifers and confirms the pivotal role of the “transitional” Triassic Voltziales that gave rise to modern groups of conifers.

Published
2022
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25. Plant macrofossils from the Rhaetian of Einberg near Coburg (Bavaria, Germany). Part 3. Conifers, incertae sedis and general discussion

Author

van Konijnenburg-van Cittert, Johanna H.A., Schmeißner, Stefan, Dütsch, Günter, Kustatscher, Evelyn, and Pott, Christian

Abstract

The plant macrofossil assemblage from a Rhaetian succession of a quarry near Einberg (Franconia, Germany), of which ferns, cycadophytes and ginkgophytes had been published earlier, comprises two conifer species (Schizolepidopsis liasokeuperianus and Stachyotaxus septentrionalis) that are unambiguously identifiable. Though both occur in small numbers of specimens only, a large number of specimens of the enigmatic gymnospermous foliage type Desmiophyllum harrisii were encountered; the true nature of this taxon is yet unknown, but evidence points towards a coniferalean affinity. The three species are described by means of macromorphology and epidermal characters. Finally, a large number of conifer cones have been found in the assemblage, which are attributed to three different types, viz., one ovuliferous cone belonging to and attached on a twig of Stachyotaxus septentrionalis; the microsporangiate cone Sphaerostrobus einbergensis sp. nov. and the ovuliferous cone Ourostrobus einbergensis sp. nov. – the latter two might belong to Desmiophyllum harrisii. A comparison between the flora from Einberg with the Rhaetian floras of adjacent localities (viz. Wüstenwelsberg, Heilgersdorf and Kipfendorf) reveals distinct regional differences within the conifers between the respective floras; this is most likely induced by local ecological disparities of varying habitats. Moreover, brief comparisons with Rhaetian floras from adjacent European areas are made, and with the Hettangian floras from Bavaria as well. Lastly, an overview of the complete Einberg plant fossil assemblage is given, including palaeoecology and palaeogeography of the whole area around Coburg during the Rhaetian.

Published
2024
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