Arabidopsis suecica

Arabidopsis suecica is a small annual herb in the mustard family (Brassicaceae) that arose as a natural allopolyploid hybrid between Arabidopsis thaliana and Arabidopsis arenosa, combining their two genomes. The plant is native to northern Europe, particularly Sweden, Finland, and adjacent Baltic regions, where it grows on rocky outcrops, dry meadows, and disturbed sandy or gravelly soils. Plants form a small basal rosette of obovate, slightly hairy leaves with shallowly toothed or pinnatifid margins, 1-4 cm long. From the rosette arise one or several slender, erect to ascending flowering stems 5-30 cm tall, sparsely branched, bearing reduced cauline leaves. The inflorescence is an elongating raceme of small, four-petaled flowers about 4-6 mm across, with petals white to faintly pinkish-lilac and yellow anthers. Fruits are slender, erect, four-angled siliques 1-3 cm long containing two rows of small brown seeds. It is widely used in plant biology as a model for studying polyploidy and hybrid speciation.