Canthium

Canthium is a genus of flowering plants in the family Rubiaceae. They are shrubs and small trees. The leaves are deciduous and the stems are usually thorny.
Distribution
Canthium species are predominantly found in Southeast Asia, especially in Thailand and the Philippines. A small number of species is found in India, Sri Lanka, and Bangladesh. Only a limited number of species is found on the African continent, especially in Southern and East Africa.
Taxonomy
Canthium was named by Jean-Baptiste Lamarck in 1785 in Encyclopédie Méthodique. The name is a latinisation of "kantankara", a Malayalam name from Kerala for Canthium coromandelicum. Kantan means "shining" and kara means "a spiny shrub". The biological type for the genus consists of specimens originally described by Jean-Baptiste Lamarck as Canthium parviflorum but this species is now included in Canthium coromandelicum. Canthium is a member of Vanguerieae, a tribe that is monophyletic and easily recognized morphologically, but in which generic boundaries were, for a long time, very unclear. Canthium was especially problematic, and until the 1980s, it was defined broadly and known to be polyphyletic. Psydrax was separated from it in 1985, as was Keetia in 1986. These were followed by Pyrostria and Multidentia in 1987. The subgenus Afrocanthium was raised to generic rank in 2004, followed by Bullockia in 2009. A few species were transferred to Canthium from Rytigynia and other genera in 2004. The genus was further reduced by the transfer of species to Peponidium and Pyrostria. In 2016, two Canthium species endemic to the Philippines were transferred to a genus of their own, Kanapia. The final circumscription of Canthium will remain in doubt until phylogenetic studies achieve greater resolution for the clade containing Canthium coromandelicum and its closest relatives.
Species
, Plants of the World Online recognises the following species:
Canthium aciculatum Ridl.
Canthium angustifolium Roxb.
Canthium arboreum Vidal
Canthium armatum
Canthium aurantiacum Merr. & L.M.Perry
Canthium berberidifolium Geddes
Canthium bipinnatum (Blanco) Merr.
Canthium brunneum (Merr.) Merr.
Canthium bugoyense
Canthium calvum Craib
Canthium cambodianum Pit.
Canthium campanulatum Thwaites
Canthium cavaleriei H.Lév.
Canthium ciliatum (D.Dietr.) Kuntze
Canthium coffeoides Pierre ex Pit.
Canthium congestiflorum Ridl.
Canthium cordatum Dillwyn
Canthium coromandelicum (Brum.f.) Alston
Canthium depressinerve Ridl.
Canthium ellipticum (Merr.) Merr.
Canthium fenicis (Merr.) Merr.
Canthium ferrugineum Craib
Canthium filipendulum Pierre ex Pit.
Canthium fraternum Miq.
Canthium glaucum Hiern
Canthium gracilipes Kurz
Canthium hainanense (Merr.) Lantz
Canthium hirtellum Ridl.
Canthium hispidonervosum (De Wild.) C.M.Evrard
Canthium horridulum Craib
Canthium horridum Blume
Canthium inerme (L.f.) Kuntze
Canthium korthalsianum Miq.
Canthium kuntzeanum Bridson
Canthium laeve Teijsm. & Binn.
Canthium lasianthoides Miq.
Canthium libericum Dinkl.
Canthium longipes Geddes
Canthium lucidum R.Br.
Canthium macrocarpum Thwaites
Canthium malayense K.M.Wong
Canthium megacarpum (Merr.) Merr.
Canthium megistocarpum Merr. & L.M.Perry
Canthium merrillianum Mabb.
Canthium mite Bartl. ex DC.
Canthium molle King & Gamble
Canthium moluccanum Roxb.
Canthium oblongum (Valeton) Kaneh.
Canthium obscurum
Canthium oliganthum (Miq.) Boerl.
Canthium oligocarpum Hiern
Canthium parvifolium Roxb.
Canthium paucinervium (Merr.) Merr.
Canthium pedunculare Cav.
Canthium perakanthus ined.
Canthium polyanthum Miq.
Canthium puberulum Thwaites ex Hook.f.
Canthium quadratum Craib
Canthium rheedei DC.
Canthium sarcocarpum (Merr.) Merr.
Canthium sarmentosum Craib
Canthium scabridum Ridl.
Canthium scandens Blume
Canthium schlechterianum Merr. & L.M.Perry
Canthium simile Merr. & Chun
Canthium sordidum (K.Schum.) Bullock
Canthium spirostylum Miq.
Canthium stellulatum Craib
Canthium strigosum Craib
Canthium strychnoides Craib
Canthium subaureum Craib
Canthium subcapitatum (Merr.) Merr.
Canthium suberosum Codd
Canthium subsessilifolium (Merr.) Merr.
Canthium tavoyanum (R.Parker) Merr.
Canthium thonningii
Canthium travancoricum Bedd.
Canthium trichophorum Quisumb. & Merr.
Canthium umbelligerum Miq.
Canthium vanwykii Tilney & Kok
Canthium villarii Vidal
Canthium violaceum Zoll. & Moritzi
References
Rubiaceae genera
Afrotropical realm flora
Indomalayan realm flora
Taxa named by Jean-Baptiste Lamarck
Taxonomy articles created by Polbot