Dasypogon R.Br.

Reference
Prodr.Fl.Nov.Holland. 263 (1810)
Name Status
Current
Image

Scientific Description

Family Dasypogonaceae.

Habit and leaf form. Herbs (tufted, sometimes arborescent). Perennial. Leaves cauline, or basal and cauline. Plants with a basal concentration of leaves (more or less acaulescent), or with neither basal nor terminal concentrations of leaves; rhizomatous (short). Pachycaul. Mesophytic, or xerophytic. Leaves small to large; alternate (crowded, scattered, terminal rosette); spiral, or distichous; leathery, or modified into spines, or ‘herbaceous’; sessile; sheathing. Leaf sheaths not tubular; with free margins. Leaves simple. Leaf blades entire; flat (to inrolled); acicular, or linear; linear (or narrow linear, gradually tapered to the apex); parallel-veined; without cross-venules; imbricate, sheathing. Leaves without stipules. Leaf blade margins scabrid. Vegetative anatomy. Plants with silica bodies. Leaf anatomy. Extra-floral nectaries absent. Stem anatomy. Secondary thickening absent.

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

Inflorescence and flower features. Flowers aggregated in ‘inflorescences’; in heads (of clusters of 4). Inflorescences scapiflorous, or not scapiflorous; terminal, or axillary (arborescent species); scape exceeding leaves, stout, hairy, with scattered bracts; peduncle elongate, slender, tough, with sparse bracts; inflorescences of arborescent species numerous on each stem, borne singly in leaf axils; inflorescence of other species single on each branch or stem, terminal; each cluster subtended by a bract; flowering starts from the equator of the inflorescence and proceeds to the apex and base. Flowers pedicellate, or sessile; bracteate (scape and floral; floral bracts navicular, exserted and pungent or not so, persistent); ebracteolate; small; regular; 3 merous; cyclic; pentacyclic. Perigone tube present, or absent. Hypogynous disk absent. Perianth of ‘tepals’; 6; 2 -whorled; isomerous; petaloid (the inner segments), or the outer segments hardened towards apex, dry; similar in the two whorls, or different in the two whorls; white, or cream, or yellow, or hyaline; fleshy, or non-fleshy. Androecial members definite in number. Androecium 6. Androecial members adnate; all equal; free of one another; 2 -whorled. Androecium exclusively of fertile stamens. Stamens 6 (in 2 whorls); all more or less similar in shape; diplostemonous; hypogynous or scarcely adhering to the base of the perianth. Anthers dorsifixed; versatile; dehiscing via longitudinal slits; introrse. Pollen shed as single grains. Gynoecium 3 carpelled. The pistil 1 celled, or 3 celled. Carpels isomerous with the perianth. Gynoecium syncarpous; eu-syncarpous; superior. Ovary unilocular, or plurilocular; 1 locular, or 3 locular (or incompletely 3); sessile. Gynoecium stylate. Styles 1; attenuate from the ovary, or from a depression at the top of the ovary; apical. Stigmas 1; 1 - lobed, or 3 - lobed. Placentation when unilocular, basal; when trilocular, axile. Ovules in the single cavity when unilocular, 1; 1 per locule; non-arillate; anatropous to campylotropous.

Fruit and seed features. Fruit non-fleshy; indehiscent; a capsule, or capsular-indehiscent; 1 seeded. Seeds endospermic. Embryo well differentiated. Testa without phytomelan.

Additional characters Pollen grains sulcate.

J. Gathe, 8 September 2016

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.