Rubus, 2021

Beek, Abraham Van De, 2021, Rubi Capenses: a further contribution to the knowledge of the genus Rubus (Rosaceae) in South Africa, Phytotaxa 515 (1), pp. 1-71 : 25

Series Rigidi Gust. ex A.Beek ser. nov.

Type:— Rubus rigidus Smith

Diagnosis: —Members of Rubus ser. Rigidi are discolorous brambles with strong mounding or scrambling primocanes and well-developed inflorescences.

Notes: — Gustafsson (1934) described R. subsect. Rigidi Veri Gustafsson (1934: 9, 55). Because the addition ‘veri’ the publication is invalid. Rubus ser. Rigidi are published here as a series, a level that corresponds better with a closed group of taxa.

Smith (1819) described R. rigidus from a sample in the Linnaean herbarium.The type consists, as usual of that time, of an inflorescence only. It is a plant with abaxially grey tomentose hairs. Most later authors attribute all discolorous Rubus in South Africa to R. rigidus , despite the great variation in such plants. Two groups can be distinguished in the Western Cape, one with long primocanes, mounding or scrambling in shrubs, and another one with rigid suberect or arching primocanes. Rubus rigidus belongs to the former group, while the latter is represented by R. chrysocarpus Chamisso & Schlechtendal (1827: 17) and R. mundtii Chamisso & Schlechtendal (1827: 18) , for instance. Because of their different characters, these groups are divided into two separate series, Rubus ser. Rigidi and R. ser. Scleri A.Beek (see below).