Hybanthus Jacq.
Enum.Syst.Pl. p2, 17. (1760)

Name Status: Current
Browse to the list of specimens for Hybanthus Jacq.

Scientific Description
J. Gathe and Leslie Watson, Friday 3 October 2008

Common name. Native Violets. Family Violaceae.

Habit and leaf form. Shrubs, or herbs, or herbaceous climbers; evergreen, or deciduous (shrubby species semi-deciduous in dry season). Perennial. Leaves cauline. Plants the herbs with a basal concentration of leaves, or with neither basal nor terminal concentrations of leaves. Stem internodes solid. Self supporting, or climbing. Mesophytic, or helophytic. Leaves fasciculate; alternate, or opposite (rarely, and sometimes clustered); spiral; petiolate to subsessile; non-sheathing; simple; epulvinate. Leaf blades dissected, or entire; when dissected, pinnatifid; pinnately veined, or palmately veined; cross-venulate. Leaves with stipules, or without stipules. Stipules free of one another; small, narrow. Leaf blade margins entire, or dentate (entire to dentate). Leaves without a persistent basal meristem. Leaf anatomy. Hairs absent. Extra-floral nectaries present (on 2 anterior anthers). Stem anatomy. Secondary thickening developing from a conventional cambial ring.

Reproductive type, pollination. Fertile flowers hermaphrodite. Unisexual flowers absent. Plants hermaphrodite. Entomophilous.

Inflorescence and flower features. Flowers solitary, or aggregated in ‘inflorescences’; when solitary, axillary; in cymes, or in racemes. The terminal inflorescence unit cymose. Inflorescences terminal, or axillary; inflorescence peduncle length approximates flower pedicel length. Flowers pedicellate; bracteate; (bi-) bracteolate; very irregular. The floral asymmetry involving the perianth, or involving the perianth and involving the androecium. Flowers 5 merous; cyclic; tetracyclic. Free hypanthium absent. Perianth with distinct calyx and corolla; 10; 2 -whorled; isomerous. Calyx present; 5; 1 -whorled; polysepalous; imbricate; unequal but not bilabiate, or regular; neither appendaged nor spurred; persistent; with the median member posterior. Corolla present; 5; 1 -whorled; polypetalous; imbricate (with descending aestivation); unequal but not bilabiate; spurred (the enlarged anterior member). Petals anterior petal broad, posterior pair linear, lateral pair broader; clawed. Androecial members definite in number. Androecium 5. Androecial members free of the perianth; coherent (via the anthers); 1 - adelphous (forming a cylinder round the ovary); 1 -whorled. Androecium exclusively of fertile stamens. Stamens 5; all more or less similar in shape; isomerous with the perianth; oppositisepalous (inserted below ovary); filantherous, or with sessile anthers (nearly). Anthers connivent, or cohering (cohering or connivent by apical or lateral connecting tissue in the form of narrow wings); adnate; dehiscing via longitudinal slits; introrse; tetrasporangiate; appendaged (often), or unappendaged. Gynoecium 3 carpelled. The pistil 1 celled. Carpels reduced in number relative to the perianth. Gynoecium syncarpous; eu-syncarpous; superior. Ovary unilocular; 1 locular. The ‘odd’ carpel anterior. Ovary sessile. Gynoecium stylate. Styles 1; apical. Stigmas 1; truncate. Placentation parietal. Ovules in the single cavity 3–15; arillate; anatropous.

Fruit and seed features. Fruit non-fleshy (coriaceous); dehiscent (splits into 3); a capsule. Capsules loculicidal and valvular. Fruit 1 celled; elastically dehiscent; 1–12 seeded. Seeds endospermic. Endosperm oily. Cotyledons 2 (flat). Embryo straight.

Etymology. From the Greek for "hump-backed" and "flower"; refers to the pouched petal.

Taxonomic Literature

Wheeler, Judy; Marchant, Neville; Lewington, Margaret; Graham, Lorraine (2002). Flora of the south west, Bunbury, Augusta, Denmark. Volume 2, dicotyledons. Australian Biological Resources Study. Canberra.

Bennett, E. M. (1999). A new subspecies of Hybanthus floribundus (Violaceae) from the eastern goldfields of Western Australia [electronic resource].

Wheeler, J. R.; Rye, B. L.; Koch, B. L.; Wilson, A. J. G.; Western Australian Herbarium (1992). Flora of the Kimberley region. Western Australian Herbarium. Como, W.A.

Marchant, N. G.; Wheeler, J. R.; Rye, B. L.; Bennett, E. M.; Lander, N. S.; Macfarlane, T. D.; Western Australian Herbarium (1987). Flora of the Perth region. Part one. Western Australian Herbarium. Perth.