Herniaria L.

Scientific Description

Family Caryophyllaceae.

Subfamily Paronychioideae, Tribe Paronychieae.

Habit and leaf form. Herbs, or shrubs (dwarf, often mat-forming); non-laticiferous and without coloured juice. ‘Normal’ plants. Leaves well developed. Plants with roots; non-succulent. Annual, or perennial. Leaves cauline. Climbing, or self supporting; scrambling (mat-forming). Mesophytic. Not heterophyllous. Leaves small; opposite, or alternate (in upper leaves, due to reduction of one of the leaves); with blades; sessile; simple; not peltate. Leaf blades entire; flat; obovate to elliptic. Mature leaf blades adaxially glabrous; abaxially glabrous. Leaves with stipules. Stipules scaly (minute). Leaf blade margins entire; flat. Leaf anatomy. Hairs absent; glandular hairs absent.

Reproductive type, pollination. Fertile flowers hermaphrodite, or functionally male and functionally female. Unisexual flowers absent, or present. Plants hermaphrodite, or monoecious.

Inflorescence and flower features. Flowers aggregated in ‘inflorescences’. Inflorescence few-flowered. Flowers in cymes. Inflorescences compound. The terminal inflorescence unit cymose. Inflorescences terminal; in cymose clusters. Flowers pedicellate; bracteate. Bracts free. Flowers minute; regular; tetracyclic, or tricyclic (rarely). Free hypanthium present (more or less perigynous). Perianth with distinct calyx and corolla, or sepaline (rarely); (4–)10(–11); 2 -whorled, or 1 -whorled (rarely); isomerous, or anisomerous (rarely). Calyx present; (4–)5(–6); 1 -whorled; polysepalous; glabrous; imbricate, or valvate (rarely); green; persistent. Corolla vestigial, or absent; (0–)4, or 5; 0 -whorled, or 1 -whorled; polypetalous; contorted, or imbricate (rarely). Petals oblong to obovate; sessile. Corolla members entire. Androecium present. Fertile stamens present. Androecium (2–)4–5. Androecial members all equal; free of one another; 1 -whorled. Androecium exclusively of fertile stamens. Stamens (2–)4–5; isomerous with the perianth, or reduced in number relative to the adjacent perianth. Anthers separate from one another; dehiscing via longitudinal slits; introrse; bilocular; tetrasporangiate. Fertile gynoecium present, or absent. Gynoecium 1 carpelled. The pistil 1 celled. Gynoecium syncarpous; synovarious to synstylovarious; superior. Ovary unilocular; 1 locular. Gynoecium shortly stylate, or non-stylate (or nearly so). Styles 1; simple. Stigmas 1; 2 - lobed, or 1 - lobed. Placentation free central, or basal. Ovules in the single cavity 1; campylotropous.

Fruit and seed features. Fruit not hairy; indehiscent, or dehiscent (irregularly); a nut. Dispersal unit the seed. Fruit 1 seeded. Perisperm present. Seeds small, or minute.

Geography, cytology, number of species. Holarctic. Adventive. Not endemic to Australia. Australian states and territories: Western Australia, South Australia, New South Wales, and Victoria. 2n=18, 36, 54, 72, 108, 126, ca 144. A genus of ca 45 species; 1 species in Western Australia; 0 endemic to Western Australia.

Additional comments. The primary shoot only consists of hypocotyl and epicotyl and the whole plant is built up by secondary branches (Bittrich 1993:207).