Phylogenetic or stratophenetic systematics? (A comment of Werneburg R. (2003): The branchiosaurid amphibians from the Lower Permian of Buxieres-les-Mines, Bourbon l'Archambault Basin (Allier, France) and their biostratigraphic significance. - Bull. Soc. geol. Fr., 174 (4), 343-349.)