Why Lycospora dominated many Pennsylvanian spore assemblages

The microspore genus Lycospora in its wider sense is produced by both heterosporous cones, Flemingites, and homosporous cones Lepidostrobus. Calculations are made of the number of microspores that are produced by cones and then by individual Pennsylvannian arborescent lycophytes. The distribution of the rooting rhizohores, Stigmaria can be extrapolated to a square kilometre of forest. A calculation of the number of spores produced in such a forest is enormous which explains why some dispersed spore floras are dominated by these spores. There are dispersed spore assemblages prepared from coal with high percentages of Lycospora. However, the methods of preparation and counting of the spores do not give enough information to make a meaningful calculation of their total numbers in the samples.