Nederlandse versie                                     Email

The Lower Liassic Flora of Bayreuth

In the region of Bayreuth (Franken, Germany) the layers of the Lower Liassic are very well exposed. The region of BayreuthTill recently these sediments were called the Rhät-Liassic layers, in which the Rhät is the uppermost formation of the Triassic and the Liassic the lowermost formation of the Jurassic. However, it has been proved now that the Rhät does not occur in the neighbourhood of Bayreuth and that the sediments are of Lower Liassic age. The layers are also called Plant sandstone. The age of the strata is roughly 200 million years.

The spots on the map indicate a couple of sites, which have yielded plant fossils in the course of time. There has been intensive collecting in this area for many years, especially in the sand quarries. Most of the sites, however, are not productive any more and besides the situation is changing frequently. According to German law the quarries must be filled up when they are finished. The dotted areas in the map indicate the Lower Liassic.
In most cases the plants have been embedded in creeks being part of a fluvial system. Plants falling in turbulent water had hardly a chance to fossilize, but in quiet waters and in still creeks the situation was more favourable. That's why the fossils are found mostly in lenses. In fact these are transverse sections of petrified creeks.
The (rather soft) rock containing the fossils is mostly whitisch, yellowish or ochre coloured, but sometimes bands with reddish or black brown tints also occur. From time to time rapid sand sedimentations have taken place, covering the creeks, plant remains inclusive. River banks, stagnant river bends and lakes have also been preserved in some cases. But the plant layers are always very local. 

Collecting
Sand quarry near Bayreuth
No fossil sites are described here, because I don't want to be responsible for the coming of too many collectors to the quarries. At the moment quarry owners sometimes give permission to collect, but it will be clear that this will change if the concourse is too large. Especially if some of the collectors will enter the quarry illegally.
To diminish the enthousiasm a bit more, I can say (and this is really true) that the lenses with fossils are difficult to find and that the fossils (with some exceptions) are not spectacular because they have often the same colour as the rock. The clarity of the photos is for a large part the merit of the contrast function in my photo editing program.

Description of the flora
Below is the list of the collected plants. Click on the name of a group to go to the descriptions of the species.

Horsetails
Neocalamites lehmannianus
Schizoneura carcinoides
Equisetites muensteri
Cycasses
Nilssonia acuminata
Nilssonia polymorpha
Pseudoctenis prossii
Ferns
Marattiopsis intermedia (Marattiaceae)
Todites princeps
(Osmundaceae)
Phialopteris tenera
(Schizaeaceae)
Selenocarpus muensterianus
(Matoniaceae)
Phlebopteris angustiloba
(Matoniaceae)
Phlebopteris muensteri
(Matoniaceae)
Thaumatopteris brauniana
(Dipteridaceae)
Dictyophyllum nilsonii
(Dipteridaceae)

Spiropteris

Ginkgos
Ginkgoites (Baiera) taeniata
Sphenobaiera spectabilis
Schmeissneria microstachys
Stachyopitys preslii
Bennettitales
Otozamites brevifolius
Conifers
Podozamites distans
Swedenborgia benkertii
Hirmeriella muensteri
Palyssia sphenolepis
Schizolepis liasokeuperianus
Seed ferns
Sagenopteris nilssoniana
Pachypteris rhomboidalis
Pachypteris saligna
Ctenozamites wolfiana
Gnetales
Desmiophyllum gothanii
Piroconites kuespertii
Bernettia inopinata
Chlamydolepis lautneri

Click here to see a complete survey of the fossil photos.

Conclusion
The Lower Liassic flora of Bayreuth may not be one of the most gorgeous ones (with exceptions), yet it gives a clear image of the situation in a plant world 200 million years ago. Ferns, cycasses, Bennettitales, ginkgos, Gnetales and conifers dominate. And there are also more ancient plants like the horsetails and the seed ferns.

If you like to see the beautiful exceptions (the museum pieces), go and visit the uppermost floor of the Museum in Bayreuth. There is an exhibition of the collection of the deceased amateur specialist Sept Hauptmann and his still active wife Traute. Indeed an homage to these two successful supercollectors.

Thanks to Prof. Han van Konijnenburg-van Cittert of Naturalis (Leyden, Holland)), Jürgen Meyer from Zwickau (Germany), Erwin and Xander Kaspers, Bert van Zuylen, Jaap Luteyn and several members of the Working Group Fossils Wageningen.

Literature