Trymalium Fenzl

Reference
Enum.Pl. p20 (1837)
Name Status
Current
Image

Scientific Description

Common name. Trymaliums. Family Rhamnaceae.

Habit and leaf form. Shrubs, or trees. ‘Normal’ plants. Leaves well developed. Plants with roots; non-succulent; unarmed; autotrophic. To 5 m high. Self supporting. Not heterophyllous. Leaves minute (T. elachophyllum), or small to medium-sized; not fasciculate; alternate; with blades; petiolate, or subsessile; with ‘normal’ orientation; simple; not peltate. Leaf blades entire; flat, or folded (lengthwise to almost hide the lower surface), or solid; semi-terete; linear, or ovate, or obovate, or oblong, or elliptic; pinnately veined. Mature leaf blades adaxially glabrous, or pubescent (sparsely); abaxially glabrous, or pubescent (white hairy, or white stellate-hairy). Leaves with stipules. Stipules scaly; persistent. Leaf blade margins entire; flat, or revolute. 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, or few-flowered. Flowers in cymes, or in racemes. Inflorescences compound. The terminal inflorescence unit cymose. Inflorescences terminal, or axillary. Flowers pedicellate; bracteate. Bracts deciduous (usually), or persistent. Flowers minute; regular; 5 merous; cyclic; tetracyclic. Free hypanthium present. Perianth with distinct calyx and corolla; 10; 2 -whorled; isomerous. Calyx present; 5; 1 -whorled; gamosepalous; lobed. Calyx lobes divided to the disk. Calyx glabrous; valvate; regular. Calyx lobes ovate. Epicalyx absent. Corolla present; 5; 1 -whorled; alternating with the calyx; polypetalous; regular. Petals hooded (but not always enclosing the anthers). Corolla members entire, or fringed (3-lobed, T. angustifolium). Androecium present. Fertile stamens present. Androecial members definite in number. Androecium 5. Androecial members adnate (inserted near the disc); 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. The pistil 1 celled. Carpels reduced in number relative to the perianth. Gynoecium syncarpous; synstylovarious; inferior, or partly inferior. Ovary plurilocular; 3 locular. Gynoecium stylate. Styles 1; apical. Stigmas 2–3 - lobed. Ovules 1 per locule (in WA); ascending; anatropous.

Fruit and seed features. Fruit aerial; 1–3 mm long; a schizocarp. Dispersal unit the seed, or the fruit. Seeds 1 per locule.

Geography, cytology, number of species. Native of Australia. Endemic to Australia. Australian states and territories: Western Australia, South Australia, Queensland, and Victoria. Northern Botanical Province and South-West Botanical Province. A genus of ca 11 species; 8 species in Western Australia; 8 endemic to Western Australia.

Etymology. From the Greek for "the eye of a needle"; refers to the three slits at the summit of the fruit when it opens.

B. Richardson, 8 September 2016

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.
  • Rye, B. L. (2000). Trymalium monospermum (Rhamnaceae), a new species from south-western Australia.
  • 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.
  • Rye, B. L. (1996). A synopsis of the genera Pomaderris, Siegfriedia, Spyridium and Trymalium (Rhamnaceae) in Western Australia.
  • 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].