Description of the female of Syrittosyrphus opacea Hull, 1944 (Diptera, Syrphidae, Eristalinae) with additional notes on the genus

The taxonomy of Syrphidae is far from being complete in the Afrotropical Region and many species have been described from a single sex only. One of these is the enigmatic monotypic genus Syrittosyrphus Hull, 1944, of which, so far, only the male of Syrittosyrphus opacea Hull, 1944 was described from the Eastern Cape Province in South Africa. Here, we re-describe the male and describe the female. We summarise all known distribution records from South Africa (Eastern Cape, KwaZulu-Natal and Limpopo Provinces) and Zimbabwe (Vumba), of which several are new. We also provide notes on the species’ ecology.