Original paper

Revision of the Messinian flora of Polenta (Romagna Apennines, Northern Italy)

Teodoridis, Vasilis; Kvaček, Zlatko; Sami, Marco


The fossil leaf material of Polenta originally described by Principi (1922, 1926) has been studied morphologically to assess the taxonomic composition of the plant assemblage and to carry out vegetation analysis. The flora of Polenta includes after the present revision 46 vascular plant taxa with 5 conifers and 41 angiosperms. Several fossil species well known from late Miocene sites of Italy, France and Greece have been detected. Most frequent are conifers, i. e., Taxodium dubium (Sternberg) Heer, Sequoia abietina (Brongniart) Knobloch, cf. Quasisequoia couttsiae (Heer) Kunzmann, Pinus spp. and representatives of Lauraceae (Daphnogene polymorpha (Al. Braun) Ettingshausen, Laurophyllumsp., Sassafras ferretianum Massalongo), Platanaceae (Platanus leucophylla (Unger) Knobloch), Fagaceae ( Fagus gussonii Massalongoemend. Knobloch & Velitzelos, Quercus psedo-castanea Göppert, Q. kubinyii (Kováts ex Ettingshausen) Czeczott, Q. drymeja Unger, Q. roburoides Gaudin), Magnoliaceae (Magnolia liblarensis (Kräusel & Weyland) Kvaček), Juglandaceae ("Juglans" acuminata Al. Braun, Pterocarya paradisiaca (Unger) Iljinskaja), Salicaceae (Populus populina (Brongniart) Knobloch, P. balsamoides Göppert, Salixsp.), Ulmaceae (Zelkova zelkovifolia (Unger) Bůžek & Kotlaba), Sapindaceae (Acer integrilobum Weber, A. tricuspidatum Bronn emend. Walther, A. cf. integerrimum (Viviani) Massalongo), Leguminosae gen. indet., and Monocotyledonae fam. et gen. indet. Noteworthy occurrences represented by one or a few samples of foliage are those of Ginkgo adiantoides (Unger) Heer, Ilex geissertii Kvaček, Teodoridis & Wang, Tilia mastajana Massalongo and flower remains described as Anthites malvaeformis Principi. The general palaeovegetation structure of the Polenta plant assemblage corresponds to the vegetation transect of the Evaporitic Messinian with swamp, riparian vegetation, and zonal "subtropical humid forest". The results of the IPR vegetation analysis for the zonal upland vegetation indicate a transitional (ecotone) vegetation type between "Broad-leaved Deciduous Forest" and "Mixed Mesophytic Forest". The Polenta plant assemblage shows a higher frequency of broad-leaved deciduous elements than of evergreen and sclerophyllous ones, which is in contradiction to the adjacent Messinian plant assemblages of Monte Tondo and Tossignano.