An unusual new species of Oxalis (Oxalidaceae) from the Knersvlakte, South Africa

Oxalis ericifolia differs from all other southern African Oxalis in having massive papillate protrusions on the adaxial leaflet epidermis, broadly swollen peduncular articulations, a wine-red androecium and an extremely short petal claw, less than one fifth the length of the total petal. Other unusual features include the red colour of the claw and the substrate-induced flattening of the bulbs. It was discovered in a unique locality from which two other endemic Oxalis species have been described. A phylogenetic analysis of the nuclear ITS region places the new species in the informally recognized Oxalis flava clade.