Trevesia is a genus of evergreen shrubs and trees in the family Araliaceae (order Apiales), native to Southeast Asia, Indochina, India, and Nepal, with one species extending into southwestern China. The genus was formally described by the Italian botanist Roberto de Visiani in 1840.
Plants are hermaphroditic and typically armed with few to many spines along stems and branches; surfaces may be glabrous or covered in stellate (star-shaped) hairs. The most distinctive feature of the genus is its large, simple leaves that are deeply palmately lobed — sometimes so deeply as to appear almost palmately compound — with a characteristic fanlike base and lobes constricted nearly to the midvein; leaf margins are serrate and stipules are ligulate, partly or fully fused.
Flowers are borne in terminal or pseudo-lateral racemes or panicles of umbels. Individual flowers have 7–12 valvate petals that often cohere and fall as a calyptra (a cap), or abscise separately. Stamens equal the petal number; the inferior ovary is 6–16-carpellate with styles fused into a short column. The fruit is a globose to ovoid drupe with depressed seeds and uniform endosperm.
The genus comprises approximately 10 species and is placed within the ivy and ginseng family Araliaceae. Well-known members include Trevesia palmata, sometimes cultivated as an ornamental for its dramatic, deeply cut foliage, and Trevesia sundaica from the Sunda Islands. All species grow in evergreen tropical forest habitats.
Distribution
Trevesia is native to Southeast Asia and Indochina, extending westward to India and Nepal, with one species (T. palmata) also found in southwestern China. All species inhabit tropical evergreen forests.
Taxonomy Notes
The genus was established by Roberto de Visiani in 1840 (Giorn. Tosc. Sci. Med. 1: 72). It belongs to the family Araliaceae (order Apiales) and is distinguished from allied genera by its non-articulate pedicels, calyptrate petals numbering 7–12, and a 6–16-carpellate ovary with a columnar style.
