Moenchia Ehrh.

Scientific Description

Family Caryophyllaceae.

Subfamily Alsinoideae, Tribe Alsineae.

Habit and leaf form. Herbs; non-laticiferous and without coloured juice. ‘Normal’ plants. Leaves well developed. Plants with roots; non-succulent; unarmed. Annual. Leaves basal and cauline. Plants with neither basal nor terminal concentrations of leaves; to 0.3 m high. Self supporting. Mesophytic. Heterophyllous. Leaves not fasciculate; opposite; with blades; shortly petiolate, or sessile; simple; not peltate. Leaf blades entire; flat; linear to ovate, or ovate to oblong. Mature leaf blades adaxially glabrous; abaxially glabrous. Leaves without stipules. Leaf blade margins entire; flat. Leaf anatomy. Hairs absent; glandular hairs absent.

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

Inflorescence and flower features. Flowers aggregated in ‘inflorescences’, or solitary (rarely). Inflorescence few-flowered. Flowers in cymes. Inflorescences compound. The terminal inflorescence unit cymose. Inflorescences terminal. Flowers pedicellate; bracteate. Bracts white margined. Flowers small; regular; tetracyclic. Free hypanthium present (shortly perigynous). Perianth with distinct calyx and corolla; 8, or 10; 2 -whorled; isomerous. Calyx present; 4, or 5; 1 -whorled; polysepalous; glabrous; valvate. Corolla present; 4, or 5; 1 -whorled; polypetalous; contorted, or imbricate (rarely); white, or blue. Petals occasionally emarginate; sessile. Corolla members entire. Androecium present. Fertile stamens present. Androecium 4(–5), or 8–10. Androecial members all equal; free of one another; 1 -whorled, or 2 -whorled. Androecium exclusively of fertile stamens. Stamens 4(–5), or 8–10; isomerous with the perianth, or diplostemonous (obdiplostemonous), or reduced in number relative to the adjacent perianth (rarely). Anthers separate from one another; dehiscing via longitudinal slits; introrse; bilocular; tetrasporangiate. Fertile gynoecium present. Gynoecium 1 carpelled. The pistil 1 celled. Gynoecium syncarpous; synovarious; superior. Ovary unilocular; 1 locular. Gynoecium stylate. Styles (3–)4, or 5; free; simple. Stigmas (3–)4, or 5; 1 - lobed. Placentation free central, or basal. Ovules campylotropous.

Fruit and seed features. Fruit ca 12 mm long; not hairy; dehiscent; a capsule. Dispersal unit the seed. Fruit 50 seeded (‘numerous’). Perisperm present. Seeds minute, or small.

Geography, cytology, number of species. Holarctic. Adventive. Not endemic to Australia. Australian states and territories: Western Australia, South Australia, New South Wales, Victoria, Australian Capital Territory, and Tasmania. 2n=38. A genus of 3 species; 1 species in Western Australia; 0 endemic to Western Australia.