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The interglacial of Neumark-Nord near Merseburg, in the Geisel valley, basin NN1, contains one of the richest and most remarkable fruit and seed floras of the middle Pleistocene with more than 190 species. Today the locality is surrounded by the Middle German and region and shows therefore some special botanical features. The fossil plants derived from washing hands of detritus ashore of an interglacial lake with periodically changing water level. A high interglacial sequence with a clear changing of the forest Succession is discernible in some profiles over the Saalian-1 till, palynologically investigated by M. SEIFERT and T LITT. The first stage of the warming phase in the development of the forest vegetation is the thermophilous oak-steppe forest with Quercus pubescens and Acer tataricum. It follows the Carpinus forest. No other interglacial is more remarkably influenced by the Middle German and region. The most important sociological key species is Acer tataricum, which nowadays is distributed in the eastern submeridional Europe (Pontian floristic region), grown here in the open forests of the Aceri tatarico-Quercetum pubescentis. The species indicates a subcontinental to submediterranean climate with warm summers. The northern borderline of the species distribution area coincides with the 18.5 to 19 degrees C-isotherme of the summer (July). Many species are submediterranean or subcontinental, Southeastern European-western Asian steppe-plants: Allium flavum, Carthamus lanatus, Chenopodium glaucum, corispermum orientale, Lavandula angustifolia, Filipendula vulgaris, Linum cf. austriacum, Linum flavum, Medicago minima, Onobrychis cf. arenaria, Onopordon acanthium, Polycnemum arvense, Portulaca oleracea, Seseli hippomarathrum, Thymelaea passerina, Verbena officinalis, Viola cf. alba, Viola rupestris. Contemporaneously, there is the proof of many halophytes, headed by the very frequent Ruppia maritima, always associated by Potamogeton pectinatus and Zannichellia palustris, which clearly indicate an open inland salt flat. The species of brackish water reeds and salt meadows followed with Bolboschoenus maritimus, Carex secalina, Ranunculus ardous, Rumex maritimus, Schoenoplectus melanospermus, and Triglochin maritimum. In the ecosystem of Neumark-Nord the interactions of flora and fauna are verifiable by the nitrophytic, ruderal herbaceous perennial associations (Prae-Onopordetalia acanthii), the semi-dry lawns and the nitrophilous shoreline herbaceous perennial associations. It was possibly initially restricted to the layers of animals or the muddy pools of games. The "Brasenia-complex" of the water-and swamp plants is a good thermophilic indicator, the association of Cypero fusci-Limoselletum aquaticae is a remarkable indicator of periodical dryness of the lake or the lakeshore.

The interglacial taphocoenosis of Neumark-Nord is so unique in Central Europe that even no comparisons are possible with well known and dated interglacials of the region between Saale and Elbe. Around the Middle German arid area in the tendency of subcontinentality only the Grabschutz interglacial near Delitzsch/Saxony with a flora of steppe and many halophytes at the climatic optimum is similar. But this interglacial is controversial in the geological classification.