Dichondra J.R.Forst. & G.Forst.

Scientific Description

Family Convolvulaceae.

Habit and leaf form. Herbs; laticiferous, or non-laticiferous and without coloured juice. Autotrophic. Perennial; plants with neither basal nor terminal concentrations of leaves. Prostrate, creeping. Helophytic, mesophytic, and xerophytic. Leaves small to medium-sized; alternate; spiral; petiolate; non-sheathing; simple. Leaf blades entire; reniform or circular-cordate; pinnately veined, or palmately veined; cross-venulate; cordate. Leaves without stipules; without a persistent basal meristem. Leaf anatomy. Hairs absent, or present (hairs bifid). Stem anatomy. Nodes unilacunar. Secondary thickening anomalous, or developing from a conventional cambial ring; via concentric cambia, or from a single cambial ring.

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

Inflorescence and flower features. Flowers solitary; axillary; bracteate. Bracts minute. Flowers bracteolate; minute to small; regular to somewhat irregular. The floral asymmetry (when noticeable) involving the perianth (K only). Flowers 5 merous; cyclic; tetracyclic. Free hypanthium absent. Hypogynous disk present; annular. Perianth with distinct calyx and corolla; 10; 2 -whorled; isomerous. Calyx 5; 1 -whorled; polysepalous, or gamosepalous (then shortly united at the base); hairy; imbricate; regular to unequal but not bilabiate (subequal); herbaceous; persistent; with the median member posterior. Corolla 5; 1 -whorled; gamopetalous; deeply lobed (lobes with edges turned inwards); valvate, or imbricate (slightly); widely campanulate, or rotate; regular; glabrous abaxially; glabrous adaxially; white, or green to yellow. Androecium 5. Androecial members adnate (to the corolla); all equal; free of one another; 1 -whorled. Androecium exclusively of fertile stamens. Stamens 5. Staminal insertion in the throat of the corolla tube. Stamens oppositisepalous. Filaments glabrous; filiform. Anthers dehiscing via longitudinal slits; introrse; tetrasporangiate. Pollen grains psilate. Gynoecium 2 carpelled. The pistil 2 celled. Gynoecium syncarpous; synstylous (in D. repens, where the ovary is divided to the base into 2 cells), or synovarious (when ovary ‘2-lobed’); superior. Ovary plurilocular; 2 locular. Gynoecium median. Styles 2; free, or partially joined; simple (filiform); ‘gynobasic’. Stigmas 2; 1 - lobed; capitate; dry type; papillate; Group II type. Placentation basal. Ovules 2 per locule; ascending; apotropous; non-arillate; anatropous.

Fruit and seed features. Fruit non-fleshy; hairy; an aggregate (in D. repens), or not an aggregate. The fruiting carpel dehiscent (opening irregularly); comprised of (1-)2 more or less free capsule-like fruitlets. Fruit when synovarious, dehiscent, or indehiscent; a capsule, or capsular-indehiscent (the capsule rounded to deeply 2-lobed, erect). Capsules irregularly 2-valved when dehiscent. Fruit 1–4 seeded. Seeds subglobular; endospermic. Endosperm oily. Seeds not conspicuously hairy. Cotyledons 2. Embryo chlorophyllous; straight, or curved. Testa smooth. Seedling. Germination phanerocotylar.

Physiology, biochemistry. Aluminium accumulation not found. Photosynthetic pathway: C₃.

Geography, cytology, number of species. Native of Australia. Not endemic to Australia. Australian states and territories: Western Australia, South Australia, Queensland, New South Wales, Victoria, Australian Capital Territory, and Tasmania. South-West Botanical Province.

Additional characters Stigmas the stigmatic area globose.