Abstract

DNA analyses may reveal groupings of species that are discordant with phylogenies constructed using morphological characters. Here, we examine the taxonomic status of what, historically, was called the Tegenaria atrica group of large house spiders: T. atrica, T. saeva, and T. duellica ( gigantea ). A recent phylogenetic analysis, based largely on European material, proposed that this group should be transferred to a new genus, Eratigena, and that a lack of morphological and mtDNA distinctiveness between constituent members indicated a single species: Eratigena atrica. The new genus is well supported but the synonymy of the three species is inconsistent with information from Britain. Here, we sequence new specimens from Britain, and examine morphologically both this and additional material from Britain, continental Europe, and North America. We test the hypothesis that, although the three species are distinct in Britain, in continental Europe hybridization may have led to their fusion into a single entity. Our mtDNA sequence data confirm the previously demonstrated small genetic distances and complex phylogenetic relationships between taxa. However, we show that three distinct morphological groupings exist across the range of the species and that, as a result, the specific names atrica s.s., saeva, and duellica should be resurrected.