Hebenstretia L.
Hebenstretia is an African genus with about 40 species (Mabberley 2008). Most occur in tropical and South Africa. At least two species are cultivated as ornamentals (Gardner 2000) but they are not hardy in western Europe. Yet another species, Hebenstretia integrifolia, has been recorded as an alien in Belgium.
The placement of Hebenstretia has long been controversial. Recent molecular studies place it in Scrophulariaceae (see for instance Kornhall & al. 2001). It was previously either accommodated in a family of its own (Hebenstretiaceae), in Globulariaceae or in Selaginaceae.
Most species of Hebenstreatia are much alike. Flowers are more or less Odontites-like but in a very dense, narrow terminal spike.
Literature:
Gardner M.F. (2000) Hebenstretia. In: Cullen J. & al. (eds.), The European Garden Flora, vol. 6. Cambridge University Press, Cambridge: 341.
Hilliard O.M. (1999) The tribe Selagineae (Scrophulariaceae). Kew: Royal Botanic Gardens, Kew: VII + 312 p.
Kornhall P., Heidari N. & Bremer B. (2001) Selagineae and Manuleeae, two tribes or one? Phylogenetic studies in the Scrophulariaceae. Plant Systematics and Evolution 228: 199-218. [available online at: http://www.bergianska.se/polopoly_fs/1.77788.1330000384!/menu/standard/file/Kornhall_et_al_2001.pdf]
Mabberley D.J. (2008) Mabberley’s plant-book (3th ed.). Cambridge University Press, Cambridge: XVIII + 1021 p.
Rössler H. (1979) Revision der Gattungen Hebenstretia L. und Dischisma Choisy (Scrophulariaceae - Selagineae). Mitt. Bot. Staatssamml. München 15: 1-160.
Rössler H. (1982) Nachtrag zur Revision der Gattung Hebenstretia (Scrophulariaceae-Selagineae). Mitt. Bot. Staatssamml. Munchen 18: 183-186.