Myosurus L.

Scientific Description

Common name. Mousetails. Family Ranunculaceae.

Subfamily Ranunculoideae, Tribe Ranunculeae.

Habit and leaf form. Herbs. ‘Normal’ plants. Leaves well developed. Plants with roots; unarmed; autotrophic. Annual. Leaves basal, or cauline. To 0.25 m high. Self supporting. Mesophytic. Not heterophyllous. Leaves medium-sized, or small; alternate; with blades; leathery; petiolate; simple. Leaf blades neither inverted nor twisted through 90 degrees; entire; flat; linear, or linear and elliptic. Mature leaf blades adaxially glabrous; abaxially glabrous. Leaves without stipules. Leaf anatomy. Hairs absent.

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

Inflorescence and flower features. Flowers solitary; not crowded at the stem bases; terminal; subsessile; small; regular; not resupinate; 5 merous. Free hypanthium absent. Perianth with distinct calyx and corolla; 10(–12); 2 -whorled; isomerous, or anisomerous. Calyx present; 5(–7); 1 -whorled; polysepalous; glabrous; spurred. Sepals linear and oblong. Corolla (honey leaves) present (in Australia); 5; 1 -whorled; polypetalous; glabrous abaxially; glabrous adaxially. Petals oblong; clawed (limb strap-like, oblong-ovate with a basal nectariferous pit). Androecium present. Fertile stamens present. Androecial members definite in number, or indefinite in number. Androecium 5–10 (or more). Stamens 5–10 (or more); isomerous with the perianth, or diplostemonous, or triplostemonous to polystemonous (rarely); filantherous. Filaments glabrous. Anthers separate from one another; dehiscing via longitudinal slits; tetrasporangiate; yellow. Fertile gynoecium present. Gynoecium 100 carpelled (‘numerous’). The pistil 100 celled (‘numerous’). Carpels increased in number relative to the perianth. Gynoecium syncarpous; synovarious; superior. Ovary plurilocular; 100 locular (‘numerous’). Gynoecium stylate. Styles free; simple; apical; persistent. Stigmas 1 - lobed. Ovules 1 per locule.

Fruit and seed features. Fruit 1–1.5 mm long; indehiscent; achene-like (3-angled). Dispersal unit the seed. Seeds endospermic.

Geography, cytology, number of species. Adventive. Not endemic to Australia. Australian states and territories: Western Australia, Queensland, New South Wales, Victoria, Australian Capital Territory, and Tasmania. South-West Botanical Province. A genus of ca 15 species; 1 species in Western Australia; M. minimus L. (var. australis (F.Muell.) Huth); 0 endemic to Western Australia.

Etymology. From the Greek for "a mouse" and "a tail"; alluding to the long slender fruiting spike.