Berteroa

de Candolle

Mém. Mus. Hist. Nat. 7: 232: 290. 1821. 1821

Common names: Hoary-alyssum
Etymology: For Carlo Giuseppe Bertero, 1789–1831, Italian physician and botanist who settled in Chile
Treatment appears in FNA Volume 7. Treatment on page 252. Mentioned on page 237, 241.

Annuals or biennials [perennials]; not scapose; pubescent, trichomes stellate, mixed with simple ones. Stems erect [ascending], usually branched distally. Leaves basal and cauline; petiolate or sessile; basal not rosulate, petiolate, blade margins entire or repand [dentate, sinuate]; cauline (middle and distal) sessile. Racemes (corymbose, several-flowered, dense), considerably elongated in fruit. Fruiting pedicels erect or divaricate, slender. Flowers: sepals erect-ascending [suberect, spreading], oblong, lateral pair not saccate basally; petals usually white, rarely yellow, obcordate, apex deeply 2-fid; stamens tetradynamous; filaments: median pair flattened basally, unappendaged, [laterally 1-toothed], lateral pair with basal toothlike appendage; anthers oblong, (apex obtuse); nectar glands (4), lateral, 1 on each side of lateral stamen. Fruits sessile, oblong, or elliptic [ovate, obovate, or orbicular], smooth, slightly inflated [or not inflated], latiseptate; valves each not veined or with obscure midvein, stellate-hairy [glabrous]; replum rounded; septum complete, (membranous); ovules 4–16 per ovary; stigma capitate, obscurely 2-lobed. Seeds biseriate, flattened [plump], margined [winged or not], lenticular or ovoid-lenticular [suborbicular]; seed coat (minutely reticulate), not mucilaginous when wetted; cotyledons accumbent. x = 8.

Distribution

Introduced; Europe, Asia.

Discussion

Species 5 (1 in the flora).

Berteroa mutabilis (Ventenat) de Candolle, native to northeastern Italy, the Balkan Peninsula, and northern Turkey, is known in North America only from a handful of collections almost all made more than a century ago as garden escapes in Kansas and Massachusetts. Although it was included by R. C. Rollins (1993), who indicated that it had not been collected for 60 years, the species apparently did not become naturalized in North America and, therefore, is not included here. From B. incana, B. mutabilis is easily distinguished by having winged instead of margined seeds, and flat and glabrous versus inflated and pubescent fruits. As indicated by I. A. Al-Shehbaz (1987), the record of B. obliqua (Smith) de Candolle from the Catskill region, New York, was based on misidentified plants of B. incana.

Selected References

None.

Lower Taxa