Myosurus minimus L.


Myosurus minimus plant

Family - Ranunculaceae

Habit - Taprooted annual forb.

Myosurus_minimus_plant2.jpgTop view.

Stems - None.

Leaves - Numerous in a basal rosette, lacking well-defined petioles, 2.0-11.5 cm long. Leaf blades simple, unlobed, linear, somewhat flattened but relatively thick, the margins entire, the surfaces glabrous.

Inflorescences - Solitary flowers at tips of stalks, these ascending or weakly erect and as long or longer than leaves.

Flowers - Actinomorphic, perfect. Sepals 5, 1.5-4.0 mm long, green or pinkish- to reddish-tinged, not persistent at fruiting, each with a slender spur 0.7-3.0 mm long, this appressed-descending along the tip of the flower stalk. Petals rarely absent, usually 5, 1.0-2.5 mm long, slender, tapered to a stalklike base, white, not persistent at fruiting. Stamens about 10, not showy, the anthers yellow. Pistils numerous (to 400) in a dense spiral, each with 1 ovule. Style present.




Fruits - Dense cylindrical aggregates of achenes, these 1-3 mm in diameter, narrowly rhombic to elliptic or oblong in profile, 3-angled in cross-section; the body 4-5 mm long, the inner angle extended as a minute, appressed-ascending beak, the outer wall thick, not noticeably veined. Receptacle becoming elongated to 15-50 mm at fruiting

Myosurus_minimus_fruits.jpgFruit aggregate.

Flowering - March - May.

Habitat - Streambanks, pond margins, swamps, marshes, fens, wet fields or other moist disturbed areas.

Origin - Native to the U.S.

Lookalikes - Plantago elongata.

Other info. - This little native is found across Missouri and most of the U.S. It is small and inconspicuous, at a quick glance looking like an emerging tuft of grass. The seeds sprout in the fall, and the seedlings persist throughout the winter as basal rosettes. The genus name Myosurus means "resembling a mouse's tail," and minimus means "very small."

Photographs taken at Pacific Palisades Conservation Area, Jefferson County, MO, 4-22-2016 (SRTurner).