Concerning the fossil record of lycopsids, the opinion is often upheld that those ancient swamp dwellers were significantly receding in favour of other plant groups during the Rotliegend. This may be due to the fact that well-preserved fossils are rare and probably ascribable to only one species of Sigillaria. Small forked leaves with some kind of fructification at their base were assigned by H.B.GEINITZ to Sigillariostrobus bifidus. They were found in the Weissig basin and in the carbonaceous schist at Saalhausen. Apparently J.T.STERZEL did not agree and named that fossil Dicranophyllum bifidum. He doubted the presence of Sigillaria at Weissig and other localities. His inventory of the Rotliegend fossils of North-West Saxony did not include Sigillaria. Subsigillaria brardii BRONGNIART was doubtlessly identified by M.BARTHEL in the Doehlen strata in 1976.

Recently, macrospores of lycopsids have been found as late as Zechstein (D.UHL, Tuebingen). Silicified lycopsid fragments as stigmaria, strobilae, and tree trunks are known from Nova Paka, some of them very well preserved. Although their stratigraphic position is not quite certain, they can be useful for comparison with the finds from Saxony.

Interest in the historical Ruedigsdorf site and its Permian lycopsids faded after the quarries went out of operation. According to A.ROTHPLETZ (1901) they were closed a number of years before. Already in 1849 A.V.GUTBIER mentioned chert with fern imprints, and COTTA’s collection at the Museum fuer Naturkunde Berlin contains chert samples from there. In his Permian monograph “Dyas” (1861), H.B.GEINITZ mentions the Ruedigsdorf chert along with “similar 6-inches thick plates from the vicinity of Saalhausen” as “uncommon and therefore likewise very remarkable strata” of the Rotliegend. Apparently GEINITZ was led by hindsight!

Looking for the possible original locations of the cherts found in Pleistocene gravel pits at Neuenmoerbitz and Schoembach, we “re-discovered” the Ruedigsdorf chert in 2002. Its typical variety, which makes up the vast majority of samples, has a layered texture in black/brown/red colours, mostly without preserved plant tissue. Its thickness varies between 3cm and more than 15cm including the light-coloured top and bottom layers. This type of chert is also found in the gravel pits, where it is mostly rounded, scratched, bleached, or changed in colour. These changes due to relocation can be small as seen on the sample P002Ho from Neuenmoerbitz.

In very rare cases, slanting illumination of chert samples of this type reveals what would not have been expected from the aspect of cut faces: lycopsid-type patterns as Stigmaria ficoides imprints and patterns of Syringodendron type! The latter is well known to the fossil collectors from Westphal D of the Lugau-Oelsnitz coal field. As a typical feature, pairs of small vascular traces are arranged in quincunx between distinct closely spaced vascular strands running along the trunk. Syringodendron-specimens are imprints of the several cortex layers between trunk surface and xylem. The samples shown here were found at Neuenmoerbitz, Ruedigsdorf and Wolftitz.

Are the laminated cherts from Ruedigsdorf possibly squeezed Sigillaria trunks? Can this be the reason why some fossil structures occasionally found in other cherts, as Psaronius roots, for example, are virtually absent? If so, then how can we identify such poorly preserved trunks without the relief on the surface of the chert layer? Not with the presently available means. So we are confronted with the possibility that there may be squeezed lycopsids in cherts from other localities without being recognized as such. As a consequence, more chert samples from Rotliegend sites should be collected and carefully inspected along with those already present in collections.

Supplement 1:

Guided by die ideas outlined above we were looking for more cherts and succeeded in the gravel pit Altenburg-Nobitz in summer 2003. Some of the samples found there showed Sigillaria not only as Syringodendron: The very distinct cortex casts suggest an affiliation with Subsigillaria brardii. A detailed description has not yet been given. Here you see some pictures of these rare fossils before publication.

Supplement 2:

It seems that lycopsids have got more surprises in store. A dull-looking piece of chert picked up at Nobitz in 2003 revealed a small patch of strange-looking tissue. In order to find out what it was, the piece was cut vertically and horizontally. While taking pictures, H.SAHM in Dresden discovered the well-known signature of paired spots in the tissue which had escaped my notice. So it turned out that incidentally a cross-cut and a tangential cut of a lycopsid cortex in Syringodendron aspect with partly preserved cellular structure(!) was obtained. It is a disturbing thought that many more beautifully preserved fossils may remain unnoticed in dull-looking lumps of chert.

Supplement 3:

As promised, a few more pictures of lycopsids from the Rotliegend of North-West Saxony are presented. With some effort we found Stigmaria ficoides imprints and one excellently preserved imprint of Subsigillaria brardii on chert surfaces. The latter closely resembles a specimen from the Doehlen basin published by M.BARTHEL, which may be the most interesting news of this contribution.

Final comment:

The scarcely distributed fossils of only one species of Sigillaria in the Rotliegend of this area are compatible with the commonly held view that the variety of lycopsids was greatly reduced. This does not exclude that these old-fashined trees with cortex trunks were still competitive with respect to tree ferns and calamites in wetlands. The finds shown here are thought to provide evidence for this.
Unfortunately, lycopsids preserved in chert are easily overlooked, and specimens with really good tissue preservation are rare exceptions (as P303Ho, for example). Other parts of Subsigillaria brardii, as well-preserved spore cones, leaves and trunks, or compressions of those, have not been found so far. The finds presented above give rise to the hope that they probably can be found in North-West Saxony, perhaps even along with other species. Would J.T.STERZEL and H.B.GEINITZ smile and shake their heads in disbelief or admiration if they could read this comment?

photographs: H.SAHM/Dresden, text & photographs: R.KRETZSCHMAR/Chemnitz