Review of Ablautus Loew, 1866 with the description of new species (Diptera: Asilidae)

The assassin-fly genus Ablautus Loew, 1866 (Diptera: Asilidae) is taxonomically revised. The genus is distinguished from other Nearctic Asilidae by having the following combination of morphological features: (1) generally small body size, ranging from 5 to 12 mm, (2) frequently covered with squamose hairs or macrosetae, (3) silver or gold pubescence that covers parts of the cuticle, (4) lack of pulvilli, and commonly the male fore tarsi have long black or brown macrosetae on the distal most tarsal segments. Ablautus was previously known from 14 described species chiefly found in California, Baja California, Arizona, New Mexico, Texas, Oregon, Washington, Nevada, and Utah. J. Wilcox published the last review of these small assassin-flies in 1966. Ablautus is currently placed in the Willistonininae together with southern African genera such as Ammodiamon Londt, 1985, and Sporadothrix Hermann, 1908, and Afrotropical and Palaearctic Sisyrnodytes Loew, 1856. The need to improve our understanding of the phylogenetic relationships among these genera spawned this taxonomic revision. New material available particularly from northern Mexico tentatively identified as new species by the collector, E. Fisher, furthermore indicated that the genus is in need of modern treatment and distributed much more widely than previously known. Over 2,000 specimens were studied, which represent 26 species, 12 of which are newly described.