Taxonomic revision of the Neotropical genus Scione Walker, 1850 (Diptera: Tabanidae)

Scione Walker, 1850, is a Neotropical genus initially proposed as a subgenus of Pangonia Latreille, 1802, monotypic for P. incompleta Macquart, 1846. Currently, Scione has 46 valid species and has an exclusively neotropical distribution. The genus has been little studied, and only two reviews have been published; one by Szilády in 1926 and another by Kröber in 1930. Here, we review the genus Scione. We provide redescriptions, diagnoses, updated distribution records, identification key for the females, illustrations and comments for each species, and, additionally, made available photographs of 81% of the type specimens of the species. Furthermore, we designate a neotype for S. costaricana Szilády, 1926 and propose the status of nomen dubium for five species (S. albohirta Kröber, 1930, S. huancabambae Kröber, 1930, S. minuta Szilády, 1926, S. picta Szilády, 1926, and S. punctata Szilády, 1926), we treat S. grandis Philip, 1943 as incertae sedis, we consider S. lurida Enderlein, 1925 as a revised synonym of S. aurulans (Wiedemann, 1830), and nine new species (S.falsibilineata sp. nov., S. longibeccus sp. nov., S. nigella sp. nov., S. philipi sp. nov., S. peruviana sp. nov., S. smithi sp. nov., S. tinajillas sp. nov., S. walkeri sp. nov., and S. wilkersoni sp. nov.) are described.