Cardiospermum L.

Scientific Description

Family Sapindaceae.

Habit and leaf form. Shrubs (or undershrub), or herbaceous climbers; laticiferous, or non-laticiferous and without coloured juice. Annual to perennial. Stem internodes solid. Self supporting, or climbing; tendril climbers (peduncle with 1 or 2 circinnate tendrils or 2 or 3 short recurved tendrils), or scrambling. Mesophytic. Leaves alternate; spiral; petiolate; non-sheathing; gland-dotted, or not gland-dotted; simple, or compound; often pulvinate; when compound, multiply compound (biternate). Leaflets elliptic, or ovate; attenuate to the base. Leaf blades when simple, dissected, or entire (lobed or pinnatifid); when simple/dissected, pinnatifid; pinnately veined; cross-venulate. Leaves without stipules. Leaf blade margins serrate, or dentate (ciliate). Leaf anatomy. Hairs present, or absent. Extra-floral nectaries absent. Stem anatomy. Secondary thickening developing from a conventional cambial ring, or anomalous.

Reproductive type, pollination. Fertile flowers functionally male and functionally female. Unisexual flowers present. Plants monoecious. Female flowers with staminodes (small), or without staminodes. Male flowers with pistillodes, or without pistillodes.

Inflorescence and flower features. Flowers aggregated in ‘inflorescences’; in cymes (or cymules), or in racemes, or in umbels (or umbel-like), or in panicles. The terminal inflorescence unit cymose. Inflorescences axillary; cymules or densely bracteate racemes towards the apex of branches, panicles often reduced to umbels. Flowers pedicellate (usually), or sessile; bracteate (small, subulate); bracteolate, or ebracteolate; small; very irregular; zygomorphic. The floral asymmetry involving the perianth and involving the androecium. Flowers 4 merous; cyclic. Free hypanthium absent. Hypogynous disk present; extrastaminal; one-sided. Perianth with distinct calyx and corolla; 8; 2 -whorled; isomerous. Calyx present; 4 (usually 2 pairs); 1 -whorled; polysepalous, or gamosepalous (usually); imbricate, or valvate; unequal but not bilabiate, or regular. Sepals elliptic (inner pair), or ovate (outer pair). Corolla present; 4 (2 pairs); 1 -whorled; appendiculate, or not appendiculate; polypetalous; imbricate; unequal but not bilabiate, or regular; white. Petals obovate. Fertile stamens present, or absent. Androecial members definite in number. Androecium 6–8. Androecial members free of the perianth; markedly unequal (in West Australian species, also a difference in size between the male and female flowers); free of one another; 2 -whorled, or 1 -whorled. Androecium of male-fertile flowers exclusively of fertile stamens. Stamens 6–8; all more or less similar in shape; diplostemonous; unilateral, opposite the disc; filantherous. Anthers dorsifixed, or basifixed; more or less versatile; dehiscing via longitudinal slits; introrse; tetrasporangiate; appendaged, or unappendaged. The anther appendages apical (by connective extension). Fertile gynoecium present, or absent. Gynoecium 3 carpelled. The pistil 3 celled. Carpels reduced in number relative to the perianth, or isomerous with the perianth. Gynoecium syncarpous; synovarious to eu-syncarpous; superior. Ovary plurilocular; 3 locular. Gynoecium stylate. Styles 1; free, or partially joined; attenuate from the ovary, or from a depression at the top of the ovary; apical. Stigmas 3 - lobed. Placentation axile to basal. Ovules 1 per locule; funicled, or sessile; pendulous, or horizontal, or ascending; arillate; hemianatropous, or anatropous, or campylotropous, or amphitropous.

Fruit and seed features. Fruit non-fleshy; dehiscent; a capsule. Capsules loculicidal. Fruit 3 celled. Seeds non-endospermic. Cotyledons 2. Embryo curved, or bent, or coiled.

Etymology. From the Greek for "heart" and "seed"; the fruit is more or less three-cornered with a heart-shaped scar on the seed.