Tinospora Miers

Scientific Description

Family Menispermaceae.

Habit and leaf form. Lianas; deciduous; non-laticiferous and without coloured juice (in Australia). ‘Normal’ plants. Leaves well developed. Plants with roots; autotrophic. Climbing. Mesophytic. Not heterophyllous. Leaves medium-sized; alternate; spiral; with blades; petiolate; simple; not peltate; epulvinate. Leaf blades neither inverted nor twisted through 90 degrees; entire; flat; ovate, or triangular. Mature leaf blades adaxially glabrous; abaxially glabrous. Leaves without stipules. Leaf blade margins entire; flat. Leaf anatomy. Hairs absent.

Reproductive type, pollination. Fertile flowers functionally male and functionally female. Unisexual flowers present. Plants dioecious. Plants homostylous.

Inflorescence and flower features. Flowers aggregated in ‘inflorescences’. Inflorescence few-flowered. Flowers in racemes, or in fascicles, or in panicles. Inflorescences compound, or simple. The terminal inflorescence unit cymose, or racemose. Inflorescences axillary. Flowers bracteate (ovate); minute, or small; regular; not resupinate; 3 merous; cyclic. Perianth with distinct calyx and corolla; 9, or 12; 3 -whorled, or 4 -whorled; isomerous. Calyx present; 6; 2 -whorled; polysepalous; green. Sepals elliptic, or ovate. Corolla present; 3, or 6; 2 -whorled, or 1 -whorled; polypetalous; valvate. Petals ovate (or ‘spathulate’). Androecium present, or absent. Fertile stamens present, or absent. Androecial members definite in number. Androecium 6. Androecial members free of one another, or coherent (very shortly adnate to corolla). Androecium exclusively of fertile stamens (but 6 staminodes only present in female flowers). Stamens 6; diplostemonous; filantherous. Anthers separate from one another; dehiscing via longitudinal slits; tetrasporangiate. Fertile gynoecium present, or absent. Gynoecium 3 carpelled. Carpels isomerous with the perianth. Gynoecium apocarpous; eu-apocarpous. Carpel non-stylate (‘stigma sessile’); apically stigmatic; 2 ovuled (‘but only 1 developing’).

Fruit and seed features. Fruit 6–10 mm long; an aggregate. The fruiting carpel indehiscent; drupaceous. Dispersal unit the seed. Fruit 1 seeded. Seeds endospermic, or non-endospermic.

Geography, cytology, number of species. Native of Australia. Endemic to Australia. Australian states and territories: Western Australia, Northern Territory, Queensland, and New South Wales. Northern Botanical Province. A genus of ca 40 species; 2 species in Western Australia; 0 endemic to Western Australia.