REVISION OF THE CONE GENUS DISCINITES FROM THE CARBONIFEROUS CONTINENTAL BASINS OF BOHEMIA

Abstract

: The cone genus Discinites is revised based on 31 specimens belonging to seven species collected from the Kladno-Rakovnik, Radnice and Lisek continental basins of central and western Bohemia, Czech Republic. The stratigraphical distribution of the cones studied ranges from Bolsovian to Westphalian D. Emendations of Discinites and the species D. hlizae and D. bohemicus are proposed. A new species, D. nemejcii, is erected. Wherever possible descriptions of in situ microspores and megaspores are included in the diagnoses. Isolated microspores represent two ontogenetic stages. Immature forms have an outer layer, with an irregular primary and secondary reticulum, enveloping a laevigate inner body. In mature spores, however, the outer layer has usually been damaged, destroyed or dissolved, and the laevigate microspores are closely comparable with species of the dispersed genus Calamospora. A second type of microspore was isolated from Discinites bohemicus. Here the inner body bears a trilete mark and the outer layer has an operculum situated above the proximal pole of the inner body. These microspores are of Vestispora-type, and previously have only been reported in situ from sphenophyllalean plants. Laevigate megaspores recovered from a number of Discinites species are comparable with the dispersed species Calamospora laevigata.