Intra- und interspezifische Differenzierungen im Genus Nodalla (Neuroptera : Berothidae) im Eremial der Westpaläarktis

Abstract

Nodalla Navas 1926 is an element of the Eremic and distributed within the West Palaearctic desert belt from northwestern Africa throughout the Arabian Peninsula to Afghanistan. The systematic position within the subfamily Berothinae is mainly based upon the morphology of the genital segments and has been well established. The genus comprises 11 valid species within two subgenera: Nodalla s str with N saharica (Esben-Petersen 1920) (m, f), N ressli (U Aspock & H Aspock 1984) (m, f), N vartianella (U Aspock & H Aspock 1984) (m, f), N geyri (Esben-Petersen 1920) (m, f), N remane (U Aspock & H Aspock 1984) (f), N gallagheri n sp (f), N striatella (Navas 1936) (f), and Costachillea Navas 1926 with N eatoni (MacLachlan 1898) (m, f), N lineata (Navas 1936) (m, f), N steffani n sp (m, f), and N hackeri n sp (f). N (N) saharica and N (C) eatoni represent polycentric superspecies, with distribution areas reaching from western Africa to Persia, and to the Arabian Peninsula respectively. Geographically correlated phena can be recognized, which may, in part, be associated with climatic fluctuations in the Pleistocene. All other species are monotypic and restricted to small distribution areas; in spite of generally only insignificant differences in the morphology of the genitalia they are probably much older. The differentiation into the two subgenera might have occurred already in the Miocene. At any rate the evolution of Nodalla has to be seen within the context of the formation of the Palaearctic Eremic zone, the origin of the genus itself is, however, unknown. The three new species are described and figured, in addition redescriptions of N saharica and N striatella are presented. The distribution areas of all species are plotted in maps.