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Pinaceous ovulate cones have an abundant fossil record since the middle Lower Cretaceous. Pinus belgica Alvin (1960) is considered the second oldest representative of the genus Pinus. This taxon has thus often been included in phylogenetic and molecular dating analyses although its age and stratigraphy are uncertain. We redescribe this important species and discuss its spatiotemporal occurrence (middle Barremian to late Albian of the Mons Basin, Belgium). Several anatomical features are updated (resin canals abaxial to vascular bundles, bract and ovuliferous scale separating medially first, resin canals distributed at the edge between pith and vascular cylinder). We show that the species does possess the diagnostic characters of Pinus (e.g. thick apophysis, dorsal umbo, resin canals abaxial to vascular tissue, bract and scale traces united at origin) and there are currently no arguments to question its inclusion within the genus Pinus. Yet, this species should be considered with caution in molecular dating analyses, as the broad temporal uncertainty is likely to affect the precision of deep nodes within Pinaceae. [ABSTRACT FROM AUTHOR]

The Ourthe valley in eastern Belgium provides the most complete exposures of the upper Famennian Condroz Group. A detailed miospore stratigraphy has been established for this succession. The lower three miospore biozones of the Upper Famennian (GF, VCo and VH Oppel Zones) are re-defined and subdivided into five new interval zones. The GF Oppel Zone which spans the Middle and Upper Famennian boundary was previously subdivided into three interval zones is now reduced to two. The highest Retispora macroretieulata (Mac) Interval Zone is now removed (due to its very sporadic occurrence) which results in the Grandispora microseta (Mic) Interval Zone of the GF Oppel Zone now being the lowest miospore interval zone of the Upper Famennian. The overlying VCo Oppel zone is subdivided into two new interval zones, the Rugospora radiata (Rad) and overlying Grandispora cornuta (Cor) interval Zones. A detailed study based on new and published material of the two nominal zonal taxa of the VCo Zone has clarified their morphology and resolved identification problems with other closely related Upper Devonian taxa. Furthermore, a biometric comparison of Grandispora cornuta with Grandispora tamarae has resulted in the specific diagnosis of G. cornuta being emended to increase its minimal spine length to 8 p.m. The biostratigraphic implications for intercontinental correlations with the Upper Famennian of North America are discussed. The overlying VH Oppel Zone is subdivided into two new interval zones, the Apiculiretusispora verrucosa (Ver) Interval Zone and the overlying Vallatisporites hystricosus (Hys) Interval Zone. All of the new miospore interval zones are closely correlated with the well established conodont zones occurring in five sections of the Ourthe Valley. The new integrated data sets provide a high resolution biostratigraphy for the Upper Famennian stratigraphic interval in eastern Belgium. [ABSTRACT FROM AUTHOR]