THE SPECIES CONCEPT IN CLAVATORACEAE (FOSSIL CHAROPHYTA) REVIEWED

In a cladistic analysis, phylogenetic lineages of the Mesozoic charoph yte family Clavatoraceae have recently been interpreted as evolutionar y species. However, a reappraisal of the Perimneste-Atopochara lineage shows the existence of several evolutionary divergences which in our opinion are incompatible with monophyly as postulated under the evolut ionary species concept. The revolution of classification brought about by application of that concept causes confusion and error, and the tr ansfer of validly named species to subspecific rank causes instability and detracts from their usefulness as stratigraphic markers. The spec ies that we accept are listed in an overall classification of the Clav atoraceae. A new combination, Globator steinhauseri (G. maillardi subs p. steinhauseri Mojon) is proposed.