Floral visitors of Astrophytum myriostigma in La Sierra El Sarnoso, Durango, Mexico

Abstract Composition and frequency of floral visitors are essential to understand pollination systems. This knowledge is perhaps more important for endangered species, such as Astrophytum myriostigma. We identified seven insect species as flower visitors of A. myriostigma in the Sierra El Sarnoso, Durango, Mexico. The most frequent visitors were Anambodera species, Phaedrotettix species, and Diadasia olivacea. Floral visits were grouped into eight types. The most common was forager–nectarivore followed by nectarivore. Peak floral visitor activity occurred between 1100h and 1300h. Floral visitor composition varied during flowering, whereas the frequency of visits did not change. We observed two sets of visits in time and space for visitor composition and four sets for visitor frequency.