Revision of the North African Hoverflies of the Genus Xanthogramma Schiner, 1861 (Diptera: Syrphidae), with Description of a New Species.

North Africa has a poorly and unevenly known hoverfly fauna. Xanthogramma Schiner, 1861 (Syrphinae, Syrphini) is represented in this territory by some scattered records of four species, Xanthogramma dives (Rondani, 1857), Xanthogramma evanescens Becker & Stein, 1913 (endemic to North Africa), Xanthogramma marginale (Loew, 1854), and Xanthogramma pedissequum (Harris, 1776). After examination of old Xanthogramma material collected in Tanger, Morocco, from the 'Museo Nacional de Ciencias Naturales, Madrid, Spain (MNCN)', specimens with distinctive morphology were spotted and found to be different from a syntype of X. evanescens collected in the same locality. Consequently, we revised all the available material of Xanthogramma from North Africa, characterised a new species, proposed a lectotype for X. evanescens, and provided an identification key to the North African species of this genus. The new species is also found in Tunisia and differs from X. evanescens in facial width, colour of the thoracic pleura, length of mesonotum hairs, wing pollinosity, and shape of the yellow maculae on tergum 2.