3. Myosurus Linnaeus, Sp. Pl. 1: 284. 1753; Gen. Pl. ed. 5, 137, 1754.
Mousetail [Greek mus, mouse, and oura, tail, from shape and texture of the fruiting head of M . minimus ]
Alan T. Whittemore
Herbs , annual. Leaves basal, simple, tapering to filiform base. Leaf blade linear or very narrowly oblanceolate, margins entire. Inflorescences terminal, solitary flowers; bracts absent. Flowers bisexual, radially symmetric; sepals not persistent in fruit, (3-)5(-8), green or with scarious margins, spurred, oblong to elliptic, lanceolate, or oblanceolate, 1.5-4 mm; petals 0-5, distinct, white, plane, linear to very narrowly spatulate, long-clawed, 1-2.5 mm; nectary present; stamens 5-25; filaments filiform; staminodes absent between stamens and pistils; pistils 10-400, simple; ovule 1 per pistil; style persistent. Fruits achenes, aggregate, sessile, prismatic, exposed face forming plane outer surface, sides faceted or curved by compression against adjacent achenes; sides not veined; beak terminal, straight, 0.05-1.8 mm. x =8.
Species 15 (5 in the flora): temperate regions worldwide.
Flowers of Myosurus are unique in the family in that the receptacle continues to elongate and, in some species, to initiate new ovaries after the flowers open and pollen is shed (D.E. Stone 1959).
Mature fruits are crucial to accurate identification of most North American species of Myosurus .
Mason, H. L. and D. E. Stone. 1957. Myosurus. In: Mason, H. L. 1957. A Flora of the Marshes of California. Berkeley. Pp. 497-505 Stone, D. E. 1959. A unique balanced breeding system in the vernal pool mouse-tails. Evolution 13: 151-174.