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Tremandra DC.

Prodr. 1:344 (1824)
Name Status

Scientific Description

Family Tremandraceae.

Habit and leaf form. Shrubs. Plants unarmed. Leaves cauline. To 0.1–2 m high. Leptocaul. Mesophytic. Leaves small, or medium-sized; not fasciculate; opposite; not decussate; not decurrent on the stems; ‘herbaceous’; not imbricate; petiolate. Petioles wingless. Leaves simple; not peltate; epulvinate. Leaf blades dorsiventral; entire; flat; obovate; cross-venulate; cordate, or rounded at the base. Mature leaf blades adaxially glabrous, or pubescent; abaxially pubescent. Leaf blade margins crenate; not prickly; flat. Leaves without a persistent basal meristem. Leaf anatomy. Hydathodes absent. Hairs present; glandular hairs absent. Unicellular hairs absent. Complex hairs present. Branched hairs present. Complex hairs stellate. Stem anatomy. Nodes unilacunar. Secondary thickening developing from a conventional cambial ring.

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

Inflorescence and flower features. Flowers solitary; axillary (on filiform peduncles); pedicellate; bracteate; small, or medium-sized; regular; 5 merous; tetracyclic. Floral receptacle not markedly hollowed. Free hypanthium absent. Perianth with distinct calyx and corolla; 10; 2 -whorled; isomerous. Calyx present; 5; 1 -whorled; polysepalous; spreading; hairy; exceeded by the corolla; neither appendaged nor spurred; red. Sepals narrowly ovate. Corolla present; 5; 1 -whorled; polypetalous; valvate; regular; hairy abaxially (towards the base); hairy adaxially (towards the base); with contrasting markings; white, or pink, or purple, or blue; non-accrescent. Petals obovate (to spathulate); not hooded; not navicular. Corolla members entire. Androecium present. Androecial members definite in number. Androecium 10. Androecial sequence not determinable. Androecial members free of the perianth; all equal; free of one another; 1 -whorled. Androecium exclusively of fertile stamens. Stamens 10; becoming exserted; all more or less similar in shape; diplostemonous; alternisepalous; both opposite and alternating with the corolla members; erect in bud. Filaments not geniculate; filiform. Anthers all alike; basifixed; incurved; non-versatile (but narrow at their junction with the filament); dehiscing via pores (opening via a terminal pore, anther tube absent); introrse; four locular (in 2 series); unappendaged (lacking an elongated tube). Gynoecium 2 carpelled. The pistil 2 celled. Carpels reduced in number relative to the perianth. Gynoecium syncarpous; eu-syncarpous; superior. Ovary plurilocular; 2 locular; sessile. Ovary summit hairy, the hairs not confined to radiating bands. Gynoecium stylate. Styles 1; apical; persistent; hairless. Styles straight in bud. Stigmas 1; 1 - lobed. Placentation axile, or apical. Ovulodes absent. Ovules 2 per locule.

Fruit and seed features. Fruit 2–7 mm long; non-fleshy; hairy; dehiscent; a capsule (circular to transversely broadly elliptical in outline). Dispersal unit the seed. Fruit 2 seeded. Seeds 2 per locule. Seeds endospermic; not mucous; compressed; small; arillate; conspicuously hairy; without a tuft of hairs. Cotyledons 2. Testa hard; hairy.

Geography, cytology, number of species. Australian. World distribution: Australia. Native of Australia. Endemic to Australia. Australian states and territories: Western Australia. South-West Botanical Province. A genus of 2 species; 2 species in Western Australia; 2 endemic to Western Australia.

Etymology. From the Greek for "a perforation, aperture" and "man, stamen"; refers to the difference from genus Tetratheca; the anthers of this genus when ripe perforate the septa.

S. Hamilton-Brown and 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..
  • 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..
  • 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]..