Phytogeography of Asturian (Westphalian D) lycophytes throughout the Euramerican belt of coalfields

Abstract

A summary is given of the lycophyte species as distributed in fifteen Euramerican coalfields during Asturian (Westphalian D) times. The datasets from the coalfields are analysed using unweighted pair group cluster analyses of Jaccard's Coefficients. Separate analyses were done on the full dataset (the full list of morphospecies) and on a more restricted dataset (only the morphospecies of vegetative organs). Three groupings of coalfields were resolved in the analyses. The two most clearly defined groupings represented the intramontane basin coalfields, and the coalfields of the lowland basins on the Variscan foreland where the lycophyte floras are well documented. The third grouping included those basins with less well-studied lycophyte floras, where the apparently low species diversity has undoubtedly affected the results. More work is needed on these poorly documented floras to produce a more rigorous phytogeographical analysis.