Tribulus zeyheri subsp. zeyheri flowers

The flowers of Tribulus zeyheri subsp. zeyheri grow long-stalked and solitary from leaf axils.

The corollas are yellow or creamy white, in picture only yellow in a small central part of the very shallow bowl. The five wedge-shaped petals have rounded tips, the petal surfaces delicately thin and slightly longitudinally wrinkled. The petals are broader than some other Tribulus species, slightly overlapping in picture.

The hard fruit, initially green, is (notoriously) covered in several rigid, conical spines that announce themselves suddenly and painfully to those who walk barefoot.

The spines are shorter than those of T. terrestris, the flowers bigger (Le Roux, et al, 2005; iNaturalist; www.kyffhauser.co.za; www.zimbabweflora.co.zw).