Stachys nemorivaga: A Neglected Stachys (Labiatae) from Africa

Abstract

New material of a species initially thought to be undescribed appears to match the description of the previously published species, Stachys nemorivaga Briq. This neglected species came to light when the two authors were revising Stachys for Flora Zambesiaca and Flora of Tropical East Africa, and looking at Stachys for the Flora of Ethiopia. Stachys nemorivaga was previously known only from the holotype (from material collected in Angola) which was destroyed in Berlin during the Second World War. It has subsequently been collected in Zambia and Zaire as well as a further collection in Angola. Stachys is a large sub-cosmopolitan genus in the Labiatae, subfamily Lamioideae (Cantino et al. 1992) which includes about 450 species (Codd 1985). The genus is mostly centred in the Mediterranean region of Europe and Turkey, although about 80 species (Epling 1934) occur in N. and S. America (32 of which are confined to N. America (Mulligan & Munro 1989). In Africa over 40 species occur in South Africa (Codd 1985), over 20 species in north Africa, 10 species in northeast tropical Africa, 8 species in south tropical Africa, 6 species in east tropical Africa, 3 species in west tropical Africa and 2 species in the Congolian region (one of which is S. nemorivaga). A number of species within the genus are widely cultivated for agricultural (Chinese Artichoke-S. affinis L.), horticultural (S. coccinea (L.) Trev., S. germanica L., S. byzantinia C. Koch. and others) and medicinal purposes (S. officinalis (L.) Trev. used in Europe, and S. cuneata Banks ex Benth. and S. linearis Burch. ex Benth. in South Africa (Codd 1985) to name but a few). Briquet (1894) placed Stachys nemorivaga in sect. Stachys [Stachyotypus) Dum.] subsect. Ruderales Benth. and then in 1896 placed it in sect. Stachys [Eustachys Briq. ] subsect. Rectae Boiss. Although Bhattercharjee (1980), proposed an infrageneric classification of Stachys, she did not consider the tropical African species in detail. In tropical Africa the native species fall within three groups (Sebsebe and Harley 1992), section Stachys, section Ambleia Benth. and a further new section which will be considered by Sebsebe & Harley in a subsequent paper. The different sections are distinguished by a different combination of trichome types and each of the sections occupy a different phytogeographical region. Section