Systematics of the colour-polymorphic spider genus Cybaeolus, with comments on the phylogeny of the family Hahniidae (Araneae)

Abstract

We revise the spider genus Cybaeolus Simon, 1884, endemic to Chile and Argentina, including three species, Cybaeolus delfini (Simon, 1904), Cybaeolus pusillus Simon, 1884, and Cybaeolus rastellus (Roth, 1967). The genus Clitistes Simon, 1902 is synonymized with Cybaeolus, and its type species Clitistes velutinus Simon, 1902 is synonymized with Cybaeolus pusillus. We provide a phylogenetic analysis of Cybaeolus and representatives of Hahniidae and outgroups, using molecular markers. Because Cybaeolus is nested within Hahniinae, we synonymize the subfamily Cybaeolinae Lehtinen, 1967 with Hahniinae Bertkau, 1878, and provide an updated diagnosis of Hahniidae using characters of the male palp and spinning organs. We trace the evolution of the characteristic transversal arrangement of spinnerets of hahniids; our results indicate that the grouped spinnerets of Cybaeolus, as well as the presence of many piriform gland spigots, is a reversion to the ancestral state found in outgroups. The morphology of the male palp of hahniids suggests that the tibial retrolateral apophysis of the male is a functional conductor of the intrommittent organ during mating. We document the colour polymorphism of the three species of Cybaeolus, which is unrelated to geographic location and time of collection, and similar morphs occur in both sexes of different species.