The spider family Leptonetidae in North America


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Publication Date

January 1974


A systematic review of spiders of the family Leptonetidae in North America is presented wit h analyses of their characters and relationships . Reasons are given for using only two generic names fo r the 44 taxa of this fauna, most of which are described as new . The subfamily Leptonetinae includes al l representatives of the world fauna in which the posterior median eyes are situated far back of th e posterior lateral eyes . The genus Leptoneta, which is the basic standard of the family and occur s widely in Palearctica, is considered to include all but three of the American species . Its disjunc t distribution in North America makes possible treatment of different faunas of four quite discret e centers of distribution . The largest fauna of 15 species occurs in the southern Appalachian Mountains , includes six epigean species and nine cavernicoles ; of the latter one from Georgia is an eyeles s troglobite and others have eyes in various stages of reduction . A dozen species from the Edward s Plateau Region of middle Texas and some outlying districts are related to those of Appalachia ; one o f the nine cavernicoles is eyeless and others have rudimentary eyes . Nine species from eastern Mexic o show more morphological variability but differ httle in basic features from those from the south - eastern United States ; two of them are blind troglobites . The five Californian representatives o f Leptoneta are all big-eyed epigean types notable for remarkable, derivative modifications of the mal e palpi of some . A new genus Archoleptoneta is given subfamily status for various unusual features . Th e posterior median eyes form a transverse row with the posterior lateral eyes in an eye formula probabl y reminescent of the ancestral stock of the family . The male palpus presents generalized features of th e bulb and especially of the tarsus which lacks a transverse groove present in various degrees of develop - ment in the Leptonetinae .Archoleptoneta is an exclusively American group so far known from thre e species in C


Journal of Arachnology, Vol. 1 (1974).