Dalla Torre, 1893: 70; Emery, 1922c: 165; Ettershank, 1966: 155; Taylor, 1987a: 29; Bolton, 1995b: 212.
Emery, 1922c: 165 (diagnosis); Brown, 1958h: 7 (all species key); Ettershank, 1966: 155 (diagnosis, review of genus); Bolton, 1995a: 1050 (census); Don, 2007: 88 (review of species); Cantone, 2017: 203 (brief male diagnosis).
Extant: 2 valid species, 0 valid subspecies (1 synonym)