Habit and leaf form. Herbs, or herbaceous climbers. Annual; plants with a basal concentration of leaves, or with neither basal nor terminal concentrations of leaves. Young stems rather angular. Rhizomatous, or tuberous. Climbing, or self supporting; when scandent, climbing via modified petiolules. Mesophytic. Leaves alternate (to sub-opposite); spiral; petiolate to sessile; non-sheathing; simple, or compound (depending on interpretation); when compound, pinnate, or bipinnate. Leaf blades when simple dissected (2–4 pinnatisect); pinnately veined. Leaves without stipules; without a persistent basal meristem. Leaf anatomy. Hairs absent. Stem anatomy. Nodes unilacunar, or tri-lacunar. Secondary thickening absent.
Reproductive type, pollination. Fertile flowers hermaphrodite. Unisexual flowers absent. Plants hermaphrodite.
Inflorescence and flower features. Flowers aggregated in ‘inflorescences’; in racemes. The terminal inflorescence unit cymose. Inflorescences terminal, or leaf-opposed. Flowers bracteate; very irregular; zygomorphic; 2 merous; cyclic. Free hypanthium absent. Perianth with distinct calyx and corolla; 6; 3 -whorled; isomerous. Calyx present, or vestigial (scale-like and closely appressed); 2; 1 -whorled; polysepalous; open in bud; not persistent (caducous). Corolla 4; 2 -whorled (2+2); polypetalous to gamopetalous (more or less connivent); imbricate; consisting of a spurred or pouched upper petal, 2 inner petals and a lower one; the inner pair narrow and connate at apex, keeled or crested on back; white, or red, or pink, or purple; spurred. Androecium 6. Androecial members branched (in that the two lateral units mostly consist each of one dithecal and two monothecal units); free of the perianth; coherent; 2 - adelphous (i.e. in two bundles of three, the bundles opposite the outer corolla members). Androecium exclusively of fertile stamens. Stamens 6. Filaments appendiculate (with basal nectaries), or not appendiculate. Anthers extrorse; unilocular (the lateral members of each triplet), or bilocular (the central member — i.e. the stamens dimorphic within each triplet); bisporangiate and tetrasporangiate. Gynoecium 2 carpelled. The pistil 1 celled. Carpels isomerous with the perianth. Gynoecium syncarpous; eu-syncarpous; superior. Ovary unilocular; 1 locular. Gynoecium transverse; stylate. Styles 1; simple (filiform); apical. Stigmas 1; dorsal to the carpels, or dorsal to the carpels and commissural; 1 - lobed, or 2 - lobed (then lobing obscure); capitate. Placentation parietal. Ovules in the single cavity 1, or 2; arillate; anatropous to campylotropous.
Fruit and seed features. Fruit non-fleshy; indehiscent; a nut (subglobular); 1 seeded. Seeds endospermic. Endosperm oily. Embryo well differentiated (small). Cotyledons 1, or 2. Embryo straight to curved.
Geography, cytology, number of species. Adventive. Australian states and territories: Western Australia, South Australia, Northern Territory, Queensland, New South Wales, Victoria, Australian Capital Territory, and Tasmania. South-West Botanical Province.