Phylogeny and taxonomy of the genera of south-western North American Euctenizinae trapdoor spiders and their relatives (Araneae: Mygalomorphae, Cyrtaucheniidae)

The primary focus of this paper is to evaluate the monophyly and intergeneric relationships of the cyrtaucheniid subfamily Euctenizinae and to a lesser degree the monophyly of Cyrtaucheniidae. Using 71 morphological characters scored for 29 mygalomorph taxa our cladistic analysis shows that Cyrtaucheniidae is likely paraphyletic with respect to the Domiothelina, the clade that comprises the Migidae, Actinopodidae, Ctenizidae, and Idiopidae. Together, the Domiothelina and Cyrtaucheniidae have been treated as the Rastelloidina clade. A strict interpretation of rastelloid classification based on our cladogram would require the establishment of four additional spider families. However, we choose to use informal names for these clades so that these taxa can be validated by subsequent studies of mygalomorph phylogeny before formal names are introduced. The phylogenetic analysis also serves as a vehicle for examining the patterns of homoplasy observed in mygalomorphs. The secondary focus of this paper is a taxonomic revision of Euctenizinae genera from the south-western United States that includes a key to its genera. The cyrtaucheniid genera Enrico and Astrosoga are considered junior synonyms of Eucteniza. Actinoxia and Nemesoides are junior synonyms of Aptostichus. At present the North American Euctenizinae comprises these seven nominal genera: Eucteniza, Neoapachella gen. nov. (Neoapachella rothi sp. nov.), Myrmekiaphila, Entychides, Promyrmekiaphila, Apomastus gen. nov. (Apomastus schlingeri sp. nov.), and Aptostichus. (C) 2002 The Linnean Society of London.