Variability of the bushcricket Ephippiger ephippiger: RAPDs and song races

The tettigoniid bushcricket, Ephippiger, shows extensive variability in morphology and behaviour in Western Europe. Several species and subspecies have been described, but many may only represent local forms of uncertain origin. Within Ephippiger ephippiger, patterns of variation differ between morphology (upon which most taxonomic forms are defined) and behaviour. There is sufficient variation in a sexual signal (calling song) within the species that 'song races' have been described, which show strong premating isolation from each other. Here RAPD markers (138 fragments from 10 primers) have been used to examine the extent and pattern of genetic differentiation within the species and between two congeneric species. Ephippiger ephippiger is clearly distinguished from its relatives. High genetic similarity has been found within E. ephippiger, Nei and Li's S averaging 0.67. Using both distance and parsimony methods resolves the relationships of the song races and morphological forms of E. ephippiger with the exception of one population. The song races represent the deepest division within the species, but the lack of concordance in different traits suggests that a complex pattern of subspecific variation is found within this species.