Acanthus sennii Chiov.

Vollesen, K. (2007). Synopsis of the Species of Acanthus (Acanthaceae) in Tropical East and Northeast Africa and in Tropical Arabia. Kew Bulletin, 62(2), 233-249. Retrieved from http://www.jstor.org/stable/20443348

Type

Ethiopia, Addis Alem to Ambo, Gaggi, Senni 1767 (holotype FT!). A photograph of the holotype is at K.

Distribution

Endemic to the highlands of Ethiopia.

Ecology

Juniperus and Podocarpus forest, montane grassland and woodland in forest glades, secondary scrub, roadsides; 1700 - 3200 m.

Conservation

Ethiopian botanists (e.g. Ensermu Kelbessa, pers. comm.) have recently expressed concern about the effects of a rapidly increasing human population upon the habitats of Acanthus sennii. It is a characteristic and striking component of the vegetation in the grassland/forest margin mosaic in the Ethiopian highlands. This is a habitat which is increasingly being turned into farmland or cleared of unwanted "weeds" to improve grazing for domestic animals. A. sennii seems to a certain extent to be able to adapt to secondary vegetation types. There are recent collections from most of the species' distribution area, but because of its striking orange red flowers it is possibly overrepresented in the herbaria. Vivero et al. (2005: 11) consider it as Near Threatened (NT).

Note

Engler (1892: 390) cites Schimper 1535 and Steudner 1533 in his diagnosis of Acanthus arboreus var. ruber. The original material of both collections was destroyed in Berlin during the war, but the Steudner 1533 sheet at Kew is an excellent specimen for a lectotype. There are two sheets of Schimper 1535 at BM; they are both A. polystachius.