Contribution
Middle Miocene fossil woods from bentonite lagerstätten of the Bavarian Upper Freshwater Molasse, Germany
Dolezych, Martina; Böhme, Madelaine; Selmeier, †Alfred
Palaeontographica Abteilung B Volume 306 Issue 1-4 (2025), p. 77 - 105
128 références bibliographiques
publié: Mar 20, 2025
publication en ligne: Feb 11, 2025
manuscrit accepté: Dec 17, 2024
manuscrit reçu: Aug 29, 2024
Abstract
The paper provides records of allochthonous fossil woods from bentonite opencast mines of the area Landshut-Mainburg in Lower Bavaria (“Niederbayern”; North Alpine Foreland Basin, Germany). The sediments containing the silicified woods are assigned to the regional lithostratigraphic unit Younger Coarse Gravel, which places the samples in the late Badenian (Langhian, Middle Miocene) xyloflora of the Upper Freshwater Molasse. The angiospermous woods as well as one coniferous (taxodiaceous) wood are anatomically described and based on the identification of sufficient diagnostic characters, they could be accommodated into fossil-species of wood. For Palaeorobinioxylon zirkelii (Platen) Selmeier an affinity to the living North American Robinia pseudoacacia L. (Fabaceae) is stated. The xylotomical structure of Dichrostachyoxylon zirkelii (Felix) Müll.-Stoll & Mädel (Fabaceae) is comparable with the extant Dichrostachys-type wood. Anatomical analysis of the coniferous wood Taxodioxylon gypsaceum (Göpp.) Kräusel provides evidence of the occurrence of Sequoia Endl. (Cupressaceae). The identification of these silicified woods reveals the specific characteristics of other xylofloras from this part of the Bavarian Molasse in the late Badenian. According to the ecological demands of their living analogues, the wood records are likely derived from different vegetation types, consisting of subxerophytic and mesophytic elements under a subtropical climate. Altogether, it corresponds to previous palaeoenvironmental characterisations of relatively xeric conditions with dry deciduous forest with some evergreen elements.
Mots-clefs
Dichrostachyoxylon • Palaeorobinioxylon • Taxodioxylon • palaeovegetation • xylotomical investigations