Sexual behavior of Diplura macrura and Ischnothele annulata (Araneae: Mygalomorphae): further evidence of diplurid polyphyly

The Dipluridae (Araneae: Mygalomorphae) is a recently redefined spider family of funnel-web spinners. Diplurid biology is poorly studied, especially regarding their sexual behavior, which is largely unknown for neotropical species. Diplura macrura (C.L. Koch, 1841) (Dipluridae) and Ischnothele annulata Tullgren, 1905 (Ischnothelidae) are medium-sized traditional diplurids from Brazil. We describe the courtship and mating behavior of these two species in detail, based on seven mating events under laboratory conditions observed for D. macrura and 10 for I. annulata. Both sexes of both species present courtship behaviors, and two novel spider sexual behaviors are described for I. annulata males (insertion lifting and post-brushing). Evidence for copulatory courtship is further observed for I. annulata. These sexual behaviors are analyzed and their importance is discussed in a phylogenetic context. Observed behaviors support the hypothesis of diplurid polyphyly, with Dipluridae closely related to Crassitarsae (Theraphosidae, Barychelidae, Nemesiidae, Cyrtaucheniidae and Microstigmatidae) and phylogenetically distant from Ischnothelidae. Additional biological information on both species is provided.