Title: Systematics of the spider genera Mallos and Mexitlia (Araneae, Dictynidae)
Authors: JASON E. BOND AND BRENT D. OPELL
Abstract: This systematic study recognizes and describes 14 species of the genus Mallos O. Pickard-Cambridge, 1902 and three species of the genus Mexitlia Lehtinen, 1967. Three species of Mallos—Mallos gertschi, Mallos chamberlini and Mallos macrolirus—and one species of Mexitlia—Mexitlia altima—are newly described. Mallos ghiggi (Caporiacco, 1938) is considered a synonym of Mexitlia grandis (O. PickardCambridge, 1896). Mexitlia grandis is considered the senior synonym of Mexitlia avara (Banks, 1898). Two species, Mallos flavovittatus (Keyserling, 1880) and Mallos nigrescens (Caporiacco, 1955) are removed from Mallos. The males of Mallos kraussi Gertsch, 1946 and Mallos blandus Chamberlin and Gertsch 1958, are described for the first time. A cladistic analysis based on 26 morphological characters produced a cladogram that supports the monophyly of Mallos and the validity of Mexitlia. This cladogram presents a phylogenetic framework for considering the evolution of social behaviour in Mallos.