The evolution of genitalia of the spider family Segestriidae (Araneae, Dysderoidea)

Abstract

Currently the spider family Segestriidae Simon, 1893 is composed of 124 described species included in four genera: Segestria Latreille, 1804, Ariadna Audouin, 1826, Gippsicola Hogg, 1900 and Citharoceps Chamberlin, 1924. Segestriidae are part of the superfamily Dysderoidea, which further includes Dysderidae C. L. Koch, 1837, Orsolobidae Cooke, 1965 and Oonopidae Simon, 1890. Spiders of these families are usually characterized by female genitalia possessing a distinct biparted copulatory bursa, which was suggested to be a putative synapomorphy of dysderoids. However, compared to the other families of Dysderoidea, the genitalia of Segestriidae are still poorly understood and detailed morphological studies focused on the four segestriid genera are still lacking. Therefore, the goal of this scholarship proposal is to perform the first comprehensive morphological study on the male and female genitalia of species from the four genera of Segestriidae (plus three possible new genera), using Micro-computed X-ray Tomography (Micro-CT) and Scanning Electron Microscopy (SEM) technologies, aiming to define terminology, infer hypothesis of homology between the structures found and to delimit characters and character-states that will be used in my current doctoral thesis on the phylogeny of Segestriidae genera. Finally, these data will serve as an ideal basis to reconstruct not only the evolution of the genitalia within Segestriidae, but also will significantly contribute to our understanding of genital evolution in the superfamily Dysderoidea. As this scholarship aims for a research stay in Germany, I plan to attend and present my results on the 30th European Congress of Arachnology, in Nottingham, England, from August 20th to 25th of 2017. (AU)