Early Paleozoic (Late Cambrian–Early Ordovician) acritarchs from the metasedimentary Baden-Baden–Gaggenau zone (Schwarzwald, SW Germany) M. Montenari a , T. Servais b, * a Institut und Museum fu ¨r Geologie und Pala ¨ontologie, Eberhard-Karls-Universita ¨t, Sigwartstrab e 10, D-72076 Tu ¨bingen, Germany b Laboratoire de Pale ´ontologie, UPRESA 8014 du CNRS, USTL, SN5, F-59655 Villeneuve-d’Ascq Cedex, France Received 24 November 1999; accepted for publication 10 January 2000 Abstract The metasediments of the low-grade metamorphosed Baden-Baden–Gaggenau zone of the northern Schwarzwald (south- western Germany) have been analyzed palynologically. From 133 samples representing different metasedimentary units, only three samples of the upper part of the Traischbach Serie provide extremely poorly-preserved palynomorphs. The assemblage consists of the galeate acritarch genera Caldariola, Cymatiogaleaand Stelliferidium, as well as specimens of diacromorph and polygonomorph acritarchs. Although determinations are difficult at the generic level and essentially impossible at the specific level, the assemblage can be attributed to an interval between the Late Cambrian and Early Ordovician. This is the first biostratigraphical age assignment for the metasediments of the Baden-Baden–Gaggenau zone, which can possibly be correlated with the Ville ´ Unit of the northern Vosges Mountains (eastern France).  2000 Elsevier Science B.V. All rights reserved. Keywords: acritarchs; Cambrian; Ordovician; Schwarzwald; Germany; biostratigraphy 1. Introduction The zone of Baden-Baden–Gaggenau in the northern part of the Schwarzwald (Black Forest, southwestern Germany) is part of the boundary between the Saxothuringian and the Moldanubian of the Central Variscan Belt of Europe (sensu Kossmat, 1927). This boundary extends from northwestern France (Matte et al., 1986) through the Vosges Mountains (Wickert and Eisbacher, 1988) and the Schwarzwald (Krohe and Eisbacher, 1988; Wickert et al., 1990) to the Bohemian Massif (Engel et al., 1983; Franke, 1989; Vollbrecht et al., 1989) and is documented by prominent magnetic and gravimetric discontinuities (Edel, 1982; Plaumann et al., 1986; Pucher, 1986; Setto and Meissner, 1987; Edel and Fluck, 1989; Wagener and Go ¨tze, 1989). Traditionally, the plate-tectonic significance of this boundary and the accompanied sedimentary and metasedimentary sequences is seen in the light of the processes forming the Variscan orogen during the Devonian and the Carboniferous. Constraints for the pre-Variscan history of the metasedimentary units of the zone of Baden-Baden–Gaggenau have been, until now, missing, because the age of the sequence was not known. However, Montenari et al. (2000) report the discovery of acritarchs in the Baden- Baden–Gaggenau zone, together with the presence of Review of Palaeobotany and Palynology 113 (2000) 73–85 0034-6667/00/$ - see front matter  2000 Elsevier Science B.V. All rights reserved. PII: S0034-6667(00)00053-1 www.elsevier.nl/locate/revpalbo * Corresponding author. Tel.: +33-(0)3-20-33-72-20; fax: +33- (0)3-20-43-69-00. E-mail address: thomas.servais@univ-lille1.fr (T. Servais).