The male and female cyathia of Euphorbia tenax grow on separate plants while many other South African Euphorbia species are not dioecious, growing cyathia of both genders on the same plant. The cyathia of E. tenax are small, only about 3 mm in diameter and yellow. There are five glands surrounding the central cyathia parts.
Cyathia are borne here in small, branched cymes on short stems. Blooming happens in spring, some say in winter as well. This photo was, however, taken end January near Van Wyksdorp, showing a longer season, albeit maybe in a localised area or from unusual climatic conditions. The plant in picture is male (Smith, et al, 2017; Vlok and Schutte-Vlok, 2015; iNaturalist; iSpot; JSTOR).