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The macroflora of Rauenberg, Baden-Württemberg, Germany, is treated monographically. The plant-bearing sediments are marine, mainly well-bedded clay- to siltstones, the so-called Fischschiefer, which are part of the Bodenheim Formation. Based on nannoplankton they are dated to nannoplankton zone NP 23 (Rupelian, Lower Oligocene). The plant remains, mainly leaves and some fructifications, are preserved as compressions. The taxonomic assignment is based on gross morphology and cuticle characteristics. The flora yields marine algae and remains of the very diverse terrestrial flora. A total of 68 taxa, including three types of algae, one cycad, 12 conifers, and 49 dicots, among them 5 palms, are described. The following fossil species are described for the first time: Laurophyllum rauenbergense, Myrica obliquifolia, Distylium metzleri, ? Berchemia altorhenana, ? Ternstroemites maritiae, Trachelospermum kelleri, Oleinites altorhenana, O. rauenbergensis, Dicotylophyllum badense, D. oechsleri, D. vesiculaeferens, D. ziegleri, ? Viscophyllum hendriksiae, and Cladites vesiculaeferens. Dicotylophyllum vesiculaeferens and Cladites vesiculaeferens bear peculiar, complex cuticular structures presumably representing salt-secreting glands. Both taxa are interpreted to derive from one plant species of yet uncertain systematic affinity. The flora bears a high proportion of broad-leaved, presumably evergreen taxa, whereas the diversity of modern Arcto-Tertiary taxa (sensu Kvaček 1994) is rather low. Most abundant are Platanus neptuni, Daphnogene cinnamomifolia, and Tetraclinis salicornioides. On the family level, Lauraceae (10 species) and Pinaceae (8) are most diverse, followed by Arecaceae (4-5), Cupressaceae, and Myricaceae (4 species each). Surprisingly, Fagaceae are documented solely by a single leaf of Eotrigonobalanus furcinervis f. haselbachensis, and the record of Pentaphyllaceae remains ambiguous (? Ternstroemites maritiae). Sloanea olmediaefolia is recorded for the first time from western parts of Europe. Remarkable is the presence of the rare cycad Ceratozamia floersheimensis. The following possible vegetation units are suggested: zonal broadleaved sclerophyllous evergreen forests and an intrazonal coastal pine-laurel-palm association on near-coastal sandy soils, as well as gallery forests along streams. No records of swampy environments were recovered. The climate may be characterised as follows: Cfa climate in transition to Cwa (and Am or Af) climate sensu Köppen, mean annual temperature 19-24°C, mean annual precipitation 1300-1700 mm, mean temperature of the warmest month 28-29°C, mean temperature of the coldest month 8-14°C, mean precipitation of the wettest month >230 mm, mean precipitation of the driest month 18-38 mm, wettest month between May and October, driest month between November and March. The warm period was the wetter one.

The fossil plant assemblage of Steinheim am Albuch, reference locality of mammal Neogene zone MN 7, is revised. The plant-bearing calcareous marls (sulcatus-beds) were deposited in an impact crater lake underlying the mammalbearing strata (trochiformis- and oxystoma-beds). Currently, MN7-8 are correlated chronostratigraphically to the Serravallian and to the Sarmatian (Central Paratethys stage). The plant fossils are preserved as mere impressions, very poor in contrast. The assemblage includes aquatic plants from the lake and its margin as well as mainly leaves of woody taxa from the terrestrial surroundings. Aquatic plants include Characeae, Cladiocarya trebovensis, Phyllites sp. - ?floating leaf, Equisetum, ?Lythraceae, ?Potamogeton geniculatus, ?Trapa, and reed and sedge-like foliage ("Typha" latissima, Monocotyledoneae). In the terrestrial flora oaks are most diverse (Quercus drymeja, Q. ?gigas, Q. kubinyii, Q. mediterranea, Q. pseudocastanea). Foliage of ?Quercus sp. is more numerous than that of all other oak species but its systematic position remains unclear. Celtis japeti, C. lacunosa, Podocarpium podocarpum, Populus balsamoides, Zelkova zelkovifolia, and Sapindales leaflets of compound leaves (Sapindales fam., gen. et sp. 1 and 2) are well documented. Acer pseudomonspessulanum vel A. integrilobum, vel Acer angustilobum, ?Carpinus sp., Buxus pliocenica, Chaneya oeningensis, cf. Daphnogene polymorpha, Leguminosites cf. hesperidum, and "Parrotia" pristina are documented based on single specimens only. Not confirmed are, among others, the following taxa described by Schweigert (1993) which would be ecologically and/or climatically relevant: Isoëtes braunii recognised here as indeterminable remain, Isoëtes sp. as leaf rhachis and petiole of compound leaves, Smilax which is Celtis japeti, Pistacia miochinensis determined here as Sapindales fam., gen. et sp. 2, Zanthoxylum as ?Sapindales fam., gen. et sp. 1, "Dikotylenrest (Phyllocladium)" as fragment of a damaged leaf, and Eichhornia as indeterminable remain. The plant assemblage at Steinheim is peculiar in several respects: it lacks conifers as well as winged fruits except for Chaneya oeningensis and a poor fragment (?Ailanthus sp.). Lauraceae are practically absent except for a single specimen (cf. Daphnogene polymorpha). Betulaceae are documented by a single leaf (?Carpinus sp.) only, while taxa otherwise characteristic of this time interval like beech, elms and willows are completely absent. Assuming that the terrestrial plant record represents the close lake surroundings, the composition of taxa, leaf physiognomy and assumed autecology indicate subhumid sclerophyllous forest environment and seasonal changes in precipitation under warm-temperate climatic conditions. The Steinheim flora is compared to the regional floristic record and to selected European plant assemblages. [ABSTRACT FROM AUTHOR]