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Accurate palyno-analysis by S. Loboziak (from 1980 to 1983) of 28 samples from the Upper Givetian to the Middle Frasnian Blacourt, Beaulieu and Ferques Formations and of 44 samples of the Upper Frasnian to the Lower Famennian Hydrequent Formation are re-evaluated. Chelinospora concinna, Verrucosisporites bulliferus, Cirratriradites jekhowskyi, Lophozonotriletes media first occurrences are major criteria for Lower and Middle Frasnian, well calibrated by conodonts. Cymbosporites acanthaceus, Rugospora bricei, Grandispora gracilis, Diducites plicabilis, Corbulispora vimineus first occurrences allow to subdivide the Upper Frasnian where conodonts are poorly present. Samarisporites triangulatus versus Auroraspora pseudocrista taxonomy and stratigraphic significance are discussed. The reconnaissance borehole Nieuwkerke-De Seule (95W152), near the limit of the Upper Palaeozoic subcrop on the Brabant Massif (West Flanders, Belgium, 75 km east of the Boulonnais), which has intersected conodont-dated Givetian/Frasnian boundary at the transition between the Bois de Bordeaux and Bovesse Formations, contained poorly preserved miospores attributed to the triangulatus–concinna (TCo) Oppel Zones. In the nearby Nieuwkerke-Noordhoek borehole (95W153), strata also assigned to the Bovesse Formation yielded better preserved miospores which demonstrate a close succession of triangulatus–concinna (TCo) and bulliferus–jekhowskyi (BJ) Oppel Zones at the transition Lower–Middle Frasnian, also known in the Beaulieu Formation in the Boulonnais. Samples from the Heuvelland groundwater monitoring well (95W175), 10 km north of Nieuwkerke, contain the bricei-acanthaceus (BA) Oppel Zone suggesting a late Frasnian age, also known in the Hydrequent Formation in the Boulonnais area and in the Booischot Formation in the Booischot borehole (59E146) from the Campine Basin (Belgium). International correlation using Frasnian miospore zonation is attempted between the Pripyat Depression in Belarus, the Timan–Pechora province in Russia and North-West China.

A miospore biozonation, including 17 new interval zones, is proposed for Devonian–Early Carboniferous stratigraphic sections in the Amazon Basin. It results from a detailed review of the coeval miospore assemblages and biohorizons in the basin. The combined use of selected Euramerican and Western Gondwanan forms as zonal and characteristic taxa permits accurate subdivision, dating and correlation of Amazon Basin palyniferous strata in terms of equivalent miospore zones of Western Europe and the Old Red Sandstone Continent. The miospore data provide new insights into such varied issues as e.g. the age and stratigraphic relationships of regional rock units, the detection and dating of intervening hiatuses, condensed sedimentary sections, anoxic phases, and resedimentation cycles. Although primarily devised to serve as a regional biozonation, the scheme presented here has a unifying character because it can be applied to other Paleozoic basins in Brazil and Western Gondwanan regions where similar miospore successions are documented. A miospore assemblage zone recently described for the early Late Carboniferous interval of the Amazon Basin is also partly reviewed and integrated with the new biozonation for the older sections.

A miospore zonal scheme for late Early - Late Devonian strata of Western Gondwana is presented. Itis based on the first occurrences of both distinctive zonal taxa or groups of taxa of the most significative biozonations of Southern Euramerica and endemic Western Gondwanan species.

The so-called “Namurian” taeniate bisaccates newly reported from the Amazon Basin of northern Brazil (Marques-Toigo et al. 1995) are demonstrated to be not older than Westphalian in the light of revised foraminiferal and palynological evidence. Nevertheless, marine microfossil data supports a slightly older age assignment (Westphalian A-B) than miospores (Westphalian C). Correlations of Carboniferous pollen assemblages in the Amazon Basin with those from the Parana Basin, in southeastern and southern Brazil, are hindered by the absence of diagnostic marine microfossils and coeval mid-Carboniferous strata in the latter.

An examination of Palaeozoic sections west of Cochabamba, and west of Lake Poopo, in western Bolivia, was conducted during a field expedition in 1991. The Rio Iglesiani valley, west of Cochabamba, surprisingly yielded a Middle Devonian age to all the visited sites, originally supposed to be Ordovician. This result is based on spores, shelly faunas (brachiopods and bivalves), and trilobites. The Copacabana de Andamarca section, west of Lake Poopo, is also dated as Middle Devonian on account of its rather rich fauna (bryozoans, corals, brachiopods, conulariids, hyolithids, tentaculitids, ostracodes, trilobites, crinoids, vertebrates). Both localities correlate to the Icla and/or Huamampampa Formation of the Tarabuco area and Subandean belt, and to the Belen and/or Sica Sica Formation of the northern Altiplano.

High-resolution miospore biostratigraphy depends upon accurate knowledge of taxonomy but also on the stratigraphical relationships between the miospore-based units and other biozones. Examples taken from the Devonian and Lower Carboniferous demonstrate that the Assemblage Zone concept and the lack of discrimination in evaluating the associated faunal and lithological data can lead to questionable conclusions. Suggestions are made for a more accurate definition of interval zones and related data.

Samples from the Menen Borehole (West Flanders, Belgium) provide new datation based on miospores for the Late Devonian and Early Carboniferous succession in the western part of the Namur Synclinorium. Despite the discontinuity and the heterogeneity (cores and cuttings of sampling), sediments of middle Famennian, uppermost Famennian (Strunian) and late middle to late Tournaisian are recognized. The implication of these data on the regional geology is emphasized.

A review of miospores, faunas and megafloras of the Lower and Middle Devonian in Libya allows new conclusions to be drawn. The application of the Ardenne-Rhenish Devonian miospore zonation in Libya gives the following results. In the North Hammadah Basin, the base of the Tadrart Formation might well be strongly diachronous depsite the lithostratigraphical correlations shown on the base of “Gamma-Ray/Neutron” logs. At least the lower part of the Tadrart Formation in borehole MG-1 is within the lowermost part of the Lochkovian not at its base. In the southern margin of the Hammadah Basin, the Tadrart and Ouan-Kasa formations are probably not older than late Emsian, maybe early Eifelian. The Ouenine Formation I is often absent there or strongly reduced. The isochroneity of the (discordant) lower limit of the Tadrart Formation across the Hammadah Basin is far to be demonstrated. The Caledonian age of the discordance on the southern margin of the Hammadah Basin can obviously be challenged. In the eastern Murzuk area, the plant-bearing Tadrart-Emi Magri formations have a Middle Devonian age according to the plant fossils themselves. The discordance which separates these formations from the Acacus Sandstone at Dor el Goussa has to be late Early Devonian or Middle Devonian because the Acacus Sandstone “Psilophytes” cannot be older than Pragian and can even be younger (Emsian). There is obviously no available argument which could counteract the fossil floral data and prove that the discordance in the eastern Murzuk has the same age as the Silurian/Devonian transitional beds in the northern Hammadah Basin.