Myosoton
Methodus, 225. 1794.
| Taxon | Illustrator ⠉ | |
|---|---|---|
 | Moenchia erecta Holosteum umbellatum subsp. umbellatum Myosoton aquaticum | Barbara Alongi Barbara Alongi Barbara Alongi |
Herbs, perennial. Taproots slender, rhizomes slender. Stems decumbent to ascending, simple or branched, terete to angular. Leaves sessile leaves clasping proximally, petiolate (proximal leaves) or sessile (most cauline leaves); blade 1-veined, ovate to broadly elliptic, not succulent, apex acute. Inflorescences axillary or terminal, open cymes; bracts paired, foliaceous, smaller. Pedicels ascending to erect, reflexed in fruit. Flowers bisexual, occasionally pistillate or reduced and sterile; perianth and androecium weakly perigynous; hypanthium minimal; sepals 5, distinct, green, ovate, 4–6 (–9) mm, herbaceous, margins green or white, herbaceous or scarious, apex acute, not hooded; petals 5, white, claw absent, blade apex deeply 2-fid; nectaries at base of filaments opposite sepals; stamens 10, occasionally fewer, arising from nectariferous disc at ovary base; filaments distinct; staminodes sometimes present, linear; styles 5 (–6), distinct, filiform, 0.7–1.8 mm, glabrous proximally; stigmas 5 (–6), linear along adaxial surface of styles, papillate (30×). Capsules ovoid to globose-ovoid, opening by 5 (–6), slightly recurved, briefly 2-fid valves; carpophore absent. Seeds 50–100, brown-blackish, reniform, laterally compressed, papillate, marginal wing absent, appendage absent. x = 14.
Distribution
Introduced; Europe, temperate Asia
Discussion
Species 1.
The combination of 5(–6) styles and a capsule opening by the same number of briefly 2-fid valves characterizes Myosoton and is not known in Stellaria. Most chromosome counts of M. aquaticum are 2n = 28, a very rare number in Stellaria.
Selected References
None.