Tritonia Ker Gawl.
Curtis's Bot.Mag. p581 (1867)

Name Status: Current
Browse to the list of specimens for Tritonia Ker Gawl.

Scientific Description
J. Gathe, Thursday 8 September 2016

Common name. Tritonias. Family Iridaceae.

Habit and leaf form. Small to medium herbs; evergreen, or deciduous. Perennial (annual leaves and flowers). Leaves basal and cauline. Plants with a basal concentration of leaves, or with neither basal nor terminal concentrations of leaves; cormous (small, globose, depressed; tunic fibrous). Helophytic to xerophytic. Leaves alternate; distichous; ‘herbaceous’, or leathery; sessile; sheathing. Leaf sheaths with free margins. Leaves foetid, or without marked odour; edgewise to the stem, or with ‘normal’ orientation; simple; epulvinate. Leaf blades entire; flat; linear, or lanceolate; narrowly elliptic to obovate, or ovate to linear (to ensiform, or falcate); parallel-veined (prominent); without cross-venules; open or closed sheaths. Leaves eligulate; without stipules. Leaf blade margins entire. Leaves with a persistent basal meristem, and basipetal development. Leaf anatomy. Hairs absent. Extra-floral nectaries absent. Stem anatomy. Secondary thickening absent.

Reproductive type, pollination. Fertile flowers hermaphrodite. Unisexual flowers absent. Plants hermaphrodite. Floral nectaries present, or absent. Nectar secretion from the perianth (from nectaries at the tepal bases). Entomophilous, or ornithophilous, or anemophilous.

Inflorescence and flower features. Flowers aggregated in ‘inflorescences’; in spikes (or spike-like). The terminal inflorescence unit cymose, or racemose. Inflorescences terminal; scape simple or branched, terete; inflorescence few-many flowered, erect or bent to one side, secund or sub-distichous; spatheate (2 per flower, membranous, green if only in part). Flowers sessile; bracteate (2 per flower, inserted at the base of the ovary, spathe-like, persistent, membranous-herbaceous to scarious, truncate, shortly dentate, subequal; outer bract 3–5 lobed or irregularly lobed; inner bract slightly smaller or equal, shortly bifid); ebracteolate; small to large; regular, or very irregular; when irregular, zygomorphic; 3 merous; cyclic; tetracyclic. Perigone tube present. Perianth of ‘tepals’; 6; 2 -whorled; isomerous; petaloid; without spots, or spotted; similar in the two whorls, or different in the two whorls; cream, or yellow, or orange, or pink. Androecial members definite in number. Androecium 3. Androecial members adnate; all equal; free of one another; 1 -whorled (representing the outer whorl). Androecium exclusively of fertile stamens. Stamens 3; all more or less similar in shape; reduced in number relative to the adjacent perianth to isomerous with the perianth; at the base of the wider part of the perianth and opposite the outer segments; alterniperianthial (opposite the outer perianth lobes). Anthers basifixed (or sub-basifixed); versatile; dehiscing via longitudinal slits; extrorse. Gynoecium 3 carpelled. The pistil 3 celled. Gynoecium partly petaloid, or non-petaloid; syncarpous; synstylovarious; inferior. Ovary plurilocular; 3 locular. The ‘odd’ carpel anterior. Gynoecium stylate. Styles 1; apical. Stigmas 3. Placentation axile. Ovules 20–50 per locule (many); arillate, or non-arillate; anatropous.

Fruit and seed features. Fruit non-fleshy (membranous); dehiscent (loculicidally from the apex); a capsule. Capsules loculicidal. Fruit 3 celled; 20–100 seeded (many). Seeds endospermic. Endosperm oily. Cotyledons 1 (coleoptile-like). Embryo straight (small). Testa without phytomelan.

Etymology. From the Greek for "weather-cock", referring to the variable orientation of the anthers.

Taxonomic Literature

  • Wheeler, Judy; Marchant, Neville; Lewington, Margaret; Graham, Lorraine (2002). Flora of the south west, Bunbury, Augusta, Denmark. Volume 1, introduction, keys, ferns to monocotyledons. Australian Biological Resources Study. Canberra.
  • Australia. Bureau of Flora and Fauna (1986). Flora of Australia. Volume 46, Iridaceae to Dioscoreaceae. Australian Govt. Pub. Service. Canberra.