First new species of the Caeculidae (Acari: Trombidiformes: Prostigmata) from Iran, with a key to the world species of Allocaeculus

A new species, Allocaeculus sirwani sp. nov. (Trombidiformes: Prostigmata: Caeculidae) is described based on adult females from Marivan city, Kurdistan Province, Iran. The new species can be distinguished from other species by the following features: the bothridial setae (bo) filiform; dorsal body setae clavate; setae c(1), a(2), d(1), d(2), e(1), e(2) present; setae c(1) normal; adanal and pseudanal plates each bearing three pairs of setae; un-pair seta hs present; palp tarsus with seven setae; epimeral setal formula 3-2-2-4/5 and spinose setal formula of leg I 3-2-1-1-2. Also, an identification key to known species of Allocaeculus is provided.