Pavonia Cav.

Scientific Description

Common name. Pavonias. Family Malvaceae.

Tribe Malvavisceae.

Habit and leaf form. Shrubs, or herbs (with a stellate indumentum). Plants unarmed. Annual, or perennial; to 0.5–1.5 m high. Mesophytic. Not heterophyllous. Leaves medium-sized; alternate; spiral; petiolate; non-sheathing; simple. Leaf blades dorsiventral; dissected (3–7 lobed), or entire; ovate, or oblong, or orbicular; usually palmately veined, or pinnately veined (rarely); cordate, or hastate, or rounded at the base. Mature leaf blades adaxially pubescent, or glabrous (or glabrescent); abaxially pubescent, or glabrous (or glabrescent). Leaves with stipules (stipules linear to filiform). Stipules caducous, or persistent. Leaf blade margins crenate, or serrate. Leaf anatomy. Hairs present. Complex hairs stellate. Extra-floral nectaries absent.

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

Inflorescence and flower features. Flowers solitary, or aggregated in ‘inflorescences’ (due to the reduction of the upper leaves); terminal, or axillary; in racemes, or in fascicles, or in panicles. Inflorescences terminal, or axillary; inflorescence of terminal or axillary solitary flowers, occasionally arranged in racemes, panicles or clusters. Flowers pedicellate; small to medium-sized; regular; 5 merous; tetracyclic. Hypogynous disk absent. Perianth with distinct calyx and corolla; 10; 2 -whorled; isomerous. Calyx present; 5; 1 -whorled; gamosepalous; lobed; 5 lobulate, or toothed; valvate; exceeded by the corolla; campanulate, or urceolate (or rotate); regular; persistent; accrescent. Calyx lobes ovate. Epicalyx present (with free, or sometimes basally connate, bracteoles, lobes ovate). Corolla present; 5; 1 -whorled; polypetalous (petals spreading or connivent, adnate to the base of the staminal column); with contrasting markings (usually with a different colour base); yellow, or orange, or red, or purple. Petals obovate. Androecium present. Androecial members indefinite in number. Androecium 50–100 (i.e. ‘many’). Androecial members adnate; all equal; coherent (connate; the filaments fused in a column surrounding the style); 1 - adelphous (the tube attached to the petals); 1 -whorled. Androecium exclusively of fertile stamens (or rather, half-stamens, each having only a half anther). Stamens 50–100. Anthers dehiscing via longitudinal slits; introrse; unilocular. Gynoecium 5 carpelled. The pistil 5 celled. Gynoecium syncarpous; synstylovarious to eu-syncarpous; superior. Ovary plurilocular; 5 locular. Gynoecium stylate. Styles 1; more than 4-branched (10-branched); apical. Stigmas 10; capitate. Placentation axile. Ovules 1 per locule.

Fruit and seed features. Fruit 7–9 mm long; non-fleshy; a schizocarp (discoid to globular, dehiscing septicidally into indehiscent mericarps leaving a persistent central axis). Mericarps 5. Dispersal unit the mericarp (membranous to woody, trigonous, laterally compressed, often keeled or winged, usually muricate or tuberculate and reticulately veined). Seeds 1 per locule (reniform in outline); 1 per mericarp. Seeds minute to small; conspicuously hairy, or not conspicuously hairy.

Geography, cytology, number of species. World distribution: pantropical, concentrated in South America. Native of Australia. Not endemic to Australia. Australian states and territories: Western Australia, Northern Territory, and Queensland. Northern Botanical Province. A genus of c. 200 species; 1 species in Western Australia; 0 endemic to Western Australia.

Etymology. After Jose Antonio Pavon (1754–1840), Spanish botanist.