Cryptic Diversity Revealed in A Revision of West Palaearctic Nomiapis and Systropha (Hymenoptera: Halictidae)

Revisionary taxonomic studies of bees from the Old World Mediterranean basin are hindered both by the apparent absence of type material for many taxa and a lack of genetic resources. The discovery of important type materials in combination with the generation of novel DNA barcodes (Cytochrome Oxidase I) has allowed cryptic diversity within the widespread taxa Nomiapis bispinosa (Brullé, 1832) and Systropha planidens Giraud, 1861 to be clarified. Nomiapis bispinosa actually consists of three distinct taxa: Nomiapis bispinosa s. str. from Morocco and Iberia to Central Asia, Nomiapis rufiventris (Spinola, 1838) spec. resurr. from Morocco to Egypt, including Sicily and Nomiapis paulyi spec. nov. from Portugal and Spain. A lectotype is designated for Nomia rufiventris Spinola, 1838. Lectotypes are designated for Nomia bispinosa Brullé, 1832 and Nomia albocincta Lucas, 1849, and type material for Nomia perforata Lucas, 1849 is clarified; both Nomiapis albocincta and Nomiapis perforata are synonymised syn. nov. with Nomiapis rufiventris. A lectotype is designated for Nomia ruficornis Spinola, 1838, and this taxon is confirmed as a synonym of Nomiapis bispinosa. Systropha planidens also consists of three distinct taxa: S. planidens from Central Europe to Iran and the European part of Russia, S. grandimargo Pérez, 1905 spec. resurr. from Portugal, Spain, and France, and S. anatolica Warncke, 1977 stat. nov. from Turkey, Syria, and northern Israel. A lectotype is designated for Systropha planidens Giraud, 1861. Systropha chrysura Pérez, 1905 is synonymised syn. nov. with S. grandimargo. These findings illustrate the extent to which our understanding of the taxonomy of Mediterranean bees remains incomplete.