Revision of the Neotropical spider genus Gephyroctenus (Araneae: Ctenidae: Calocteninae)

Gephyroctenus Mello-Leitão, 1936 (type species G. philodromoides Mello-Leitão, 1936) is revised. Three species formerly described in this genus are synonymized with species from other genera: G. kolosvaryi Caporiacco, 1947, with Acanthoctenus spinipes Keyserling, 1877, G. parvus Caporiacco, 1947, with Phymatoctenus comosus Simon, 1897, and G. vachoni Caporiacco, 1955, with Caloctenus gracilitarsis Simon, 1897. Eight new species are described: G. portovelho sp. nov., from the States of Rondônia and Amazonas, Brazil; G. divisor sp. nov. and G. acre sp. nov., from the State of Acre, Brazil; G. atininga sp. nov., G. esteio sp. nov. and G. mapia sp. nov., from the State of Amazonas, Brazil; G. juruti sp. nov., from the Department of Loreto, Peru and the State of Pará, Brazil; G. panguana sp. nov., from the Department of Huanuco, Peru. The genus can be distinguished by the presence of a cymbial retrolateral groove, retrolateral origin of embolus, embolus long and thin, median apophysis with a subdistal hook, and hyaline projection close to the embolus base in the male palp and by the fused median and lateral fields in a single epigynal plate, copulatory opening located dorsally in an atrium, and elongated copulatory ducts surrounding the spermathecae in the female epigynum. Field observations on the hunting behavior on ants in trumpet trees (Cecropia) are provided for two species, G. philodromoides and G. mapia sp. nov.