Ontogeny, variation, and synonymy in North AmericanCybaeusspiders (Araneae: Cybaeidae)

Ontogeny, interspecific homogeneity, and intraspecific variability of female genitalic and other characters of North AmericanCybaeusL. Koch spiders are described and used to resolve taxonomic problems in the genus. Ontogenetic changes in spermathecal duct morphology occur as females mature and age. Three distinct ontogenetic stages are described: pre-epigynum/pre-vulva, subadult / teneral adult, and mature adult. Concordant with aspects of sexual selection theory, closely related females may be morphologically indistinguishable. ManyCybaeusspecies exhibit a wide range of body size. Within single species, ontogenetic stages and outlier size classes have been described as separate species. Species with similar females have been lumped under one name. Based on this, 10 new synonyms are proposed for North AmericanCybaeus:C. adenoidesSchenkel =C. grizzlyiSchenkel;C. chaudiusExline andC. hatchiExline= C. shoshoneusChamberlin and Ivie;C. exlineaeChamberlin and Ivie =C. bulbosusExline;C. hystrixChamberlin and Ivie =C. cribelloidesChamberlin and Ivie;C. janusChamberlin and Ivie =C. eutypusChamberlin and Ivie;C. marinensisChamberlin and Ivie andC. angelusChamberlin and Ivie =C. consociusChamberlin and Ivie; andC. olympiaeExline andC. tiusChamberlin and Ivie =C. reticulatusSimon. In addition, four old synonyms are rejected:C. grizzlyiSchenkel andC. adenoidesSchenkel ≠C. adenesChamberlin and Ivie;C. patritusBishop and Crosby andC. silicisBarrows ≠C. giganteusBanks.