Subspecies, varieties, forms and cultivars of plants belonging to the Portulaca oleracea group

Portulaca oleracea is a polyploid complex, with diploid, tetraploid and hexaploid forms (2n = 18, 36, 54). Danin et al. (1978) divided the complex into seven subspecies on the basis of seed size and patterning, relating these to different ploidy levels: subsp. oleracea, subsp. impolita Danin & H. G. Baker, subsp. granulatostellulata Danin & H. G. Baker, subsp. nicaraguensis Danin & H. G. Baker, subsp. nitida Danin & H. G. Baker, subsp. papillatostellulata Danin & H. G. Baker, and subsp. stellata Danin & H. G. Baker. The subspecies are not geographically separated, and even within the same flora area it is possible to recognise several of these seed types, which sometimes grow together. P. oleracea (purslane) has been used as a vegetable since ancient times. The cultivated form, subsp. sativa (Haw.) Celak, distinguished by larger seeds over 1 mm long, is probably a selection from subspecies oleracea.

• Portulaca oleracea L.: (subsp. oleracea) 2n= 54
• Portulaca oleracea subs. africana Danin & Baker: 2n= 18
• Portulaca oleracea subs. granulatostellulata (Poelln.) Danin & Baker: 2n= 36
• Portulaca oleracea subs. impolita Danin & H.G.Baker: 2n= 54 (?)
• Portulaca oleracea subs. nicaraguensis Danin & H.G.Baker: 2n= 18
• Portulaca oleracea subs. nitida Danin & H.G.Baker: 2n= 36
• Portulaca oleracea subs. papillatostellulata Danin & H.G.Baker: 2n= 54
• Portulaca oleracea subs. sativa (Haw.) ?elak.: 2n= 54
• Portulaca oleracea subs. stellata Danin & H.G.Baker: 2n= 54