Acanthaceae
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| Missing image Odontonema_flwrs.jpg Odontonema cuspidatum Flowers of Odontonema cuspidatum | ||||||||||
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The Family Acanthaceae Juss. (Acanthus family) is a taxon of dicotyledonous flowering plants containing some 234-250 genera and about 2500 species. Most are tropical herbs, shrubs, or twining vines; some are spiny. Only a few species are distributed in temperate regions.
Plants in this family have simple, opposite, decussate leaves with entire (or sometimes toothed or lobed) margins. The leaves may contain cystoliths, seen as streaks in the surface. Flowers are perfect, zygomorphic to nearly actinomorphic, these arranged in an inflorescence that is either a spike, raceme, or cyme. Typically there is a colorful bract subtending each flower; in some species the bract is large and showy. The calyx is usually 4-5 lobed; the corolla tubular, 2-lipped or 5-lobed; stamens either 2 or 4 arranged in pairs and inserted on the corolla; and the ovary superior, 2-carpellate, with axile placentation. The fruit is a two-celled capsule, dehiscing somewhat explosively. In most species, the seeds are attached to a small, hooked stalk (a modified funiculus called a jaculator) that ejects them from the capsule. Seeds non-endospermous with large embryos.
A species well-known to temperate gardeners is Acanthus mollis or Bear's breech: perennials with big (up to 1 m or 3 ft tall) leaves and equally tall flower spikes. Tropical genera familiar to gardeners include Thunbergia and Justicia.
Genera
Acanthus L. -- bear's breech
Andrographis Wallich ex Nees -- false waterwillow
Anisacanthus Nees -- Desert honeysuckle
Aphelandra R. Br.
Asystasia Blume
Barleria L. -- Philippine violet
Barleriola Oerst.
Blechum P. Br.
Carlowrightia Gray -- wrightwort
Dicliptera Juss. -- foldwing
Dyschoriste Nees -- snakeherb
Elytraria Michx. -- scalystem
Eranthemum L.
Graptophyllum Nees
Hemigraphis Nees
Henrya Nees ex Benth.
Holographis Nees
Hygrophila R. Br. -- swampweed
Hypoestes Soland. ex R. Br.
Justicia L. -- justica, water-willow
Nelsonia R. Br.
Odontonema Nees -- toothedthread
Oplonia Raf.
Pachystachys Nees
Pseuderanthemum Radlk.
Ruellia L. -- wild petunia
Sanchezia Ruiz & Pavón
Siphonoglossa Oerst. -- tubetongue
Stenandrium Nees -- shaggytuft
Teliostachya Nees
Tetramerium Nees
Thunbergia Retz.
Yeatesia Small -- bractspike
and about 200 more.
Ref: ITIS 34350 (http://www.itis.usda.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=34350) 2002-09-07
For full list, see Kew (http://www.rbgkew.org.uk/cgi-bin/web.dbs/genlist.pl?ACANTHACEAE)de:Akanthus
es:Acanto
fr:Acanthacée