Spinacia

Linnaeus

Sp. Pl. 2: 1027. 1753.

,

Gen. Pl. ed. 5, 452. 1754.

Common names: Spinach
Etymology: Latin spina, spine, in reference to spiny fruit, or Persian ispanakh, spinach
Treatment appears in FNA Volume 4. Treatment on page 302. Mentioned on page 260.

Herbs, annual or biennial, monoecious, glabrous. Stems erect, not branched, not jointed, not armed, not fleshy. Leaves basal or alternate, petiolate; blade triangular-hastate to ovate, sometimes with elongated lobes, margins entire or dentate, apex acute. Inflorescences: pistillate flowers sessile in leaf axils; staminate flowers in dense terminal spikes. Flowers unisexual, rarely bisexual; staminate flowers with perianth segments 4–5, stamens 4–5; pistillate flowers enclosed by 2 accrescent or connate bracts, perianth absent, stigmas 4–5. Fruiting structures enlarged and hardened bracteoles enclosing achenes; pericarp adherent. Seeds vertical, seed coat dark, spiny or smooth; hardened bracteoles serving as seed coat; embryo annular; perisperm copious. x = 6.

Distribution

Introduced; Eurasia.

Discussion

Species 3 (1 in the flora).

The chromosome base number of six is unusual in the Chenopodiaceae. B. L. Turner (1994b) suggested that members with a base of nine, the most common number in the family, may be derived.

Selected References

None.

Lower Taxa