Pomaderris Labill.
Nov.Holl.Pl. 1:61 (1805)

Name Status: Current
Browse to the list of specimens for Pomaderris Labill.

Scientific Description
B. Richardson, Thursday 8 September 2016

Common name. Pomaderris. Family Rhamnaceae.

Habit and leaf form. Shrubs, or trees. ‘Normal’ plants. Leaves well developed. Plants with roots; non-succulent; unarmed; autotrophic. To 4.5 m high. Self supporting. Not heterophyllous. Leaves small (in WA); alternate; with blades; leathery; petiolate; simple; not peltate. Leaf blades entire; flat; ovate, or oblong, or elliptic (or emarginate); pinnately veined. Mature leaf blades adaxially glabrous, or scabrous, or pubescent; abaxially woolly. Leaves with stipules. Stipules scaly; caducous. Leaf blade margins entire. Leaf anatomy. Hairs present, or absent; complex hairs present, or absent. Complex hairs stellate.

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

Inflorescence and flower features. Flowers aggregated in ‘inflorescences’. Inflorescence many-flowered. Flowers in cymes, or in umbels, or in panicles. Inflorescences compound. The terminal inflorescence unit cymose. Inflorescences terminal, or axillary; pendent. Flowers pedicellate; bracteate. Bracts deciduous. Flowers minute, or small; regular; 5 merous; cyclic; tetracyclic, or tricyclic. Free hypanthium present. Perianth with distinct calyx and corolla, or sepaline; 10, or 5; 2 -whorled, or 1 -whorled. Calyx present; 5; 1 -whorled; gamosepalous; lobed; glabrous, or hairy; valvate; regular. Epicalyx absent. Corolla present, or absent; 5; 1 -whorled; alternating with the calyx; polypetalous; regular. Petals hooded, or not hooded. Androecium present. Fertile stamens present. Androecial members definite in number. Androecium 5. Androecial members adnate (to the floral tube); free of the gynoecium; free of one another; 1 -whorled. Stamens 5; all more or less similar in shape; isomerous with the perianth; alternisepalous; filantherous. Anthers separate from one another; dehiscing via longitudinal slits; bilocular; tetrasporangiate. Fertile gynoecium present. Gynoecium 3 carpelled, or 2 carpelled (P. bilocularis). The pistil 1 celled. Carpels reduced in number relative to the perianth. Gynoecium syncarpous; synstylovarious; inferior, or partly inferior. Ovary plurilocular; 3 locular, or 2 locular. Ovary summit hairy, the hairs not confined to radiating bands, or glabrous. Gynoecium stylate. Styles 1; apical. Stigmas 3 - lobed, or 2 - lobed. Ovules 1 per locule (in WA); ascending; anatropous.

Fruit and seed features. Fruit aerial; a schizocarp. Dispersal unit the seed, or the fruit. Seeds 1 per locule.

Geography, cytology, number of species. Native of Australia. Endemic to Australia, or not endemic to Australia. Australian states and territories: Western Australia, South Australia, Queensland, New South Wales, Victoria, and Tasmania. South-West Botanical Province. A genus of ca 68 species; 7 species in Western Australia; 5 endemic to Western Australia.

Etymology. From the Greek for "lid, cover" and "a covering of leather or skin"; refers to the membranous valves of the fruit.

Taxonomic Literature

  • Grieve, B. J.; Blackall, W. E. (1998). How to know Western Australian wildflowers : a key to the flora of the extratropical regions of Western Australia. Part II, Dicotyledons (Amaranthaceae to Lythraceae). University of W.A. Press. Nedlands, W.A.
  • Walsh, N. G.; Coates, F. (1997). New taxa, new combinations and an infrageneric classification in Pomaderris (Rhamnaceae).
  • Rye, B. L. (1996). A synopsis of the genera Pomaderris, Siegfriedia, Spyridium and Trymalium (Rhamnaceae) in Western Australia.
  • Walsh, N. G. (1994). Pomaderris brevifolia (Rhamnaceae), a new species from south-west Western Australia.