Chalcanthus Boissier, Fl. Orient. 1: 211. 1867.
Ihsan A. Al-Shehbaz
Tribe: Eutremeae Al-Shehbaz, Beilstein & E.A. Kellogg, Pl. Syst. Evol. 259. 112. 2006.
Name derivation: from Greek chalkos, copper, and anthos, flower, in reference to flower color.
Type species: C. renifolius Boissier
Herbs, perennial, with thick, cylindrical or tuberous rootstock covered apically with persistent fibrous remains of petiolar bases, glaucous. Trichomes absent or sometimes simple and present at pedicel apex and sepals base. Multicellular glands absent. Stems erect, simple or baranched. Basal leaves long petiolate, simple, entire, cordate or reniform to orbicular; lowermost cauline leaves petiolate, middle ones sessile, amplexicaul. Racemes 2−10-flowered, ebracteate, corymbose, elongated considerably in fruit; rachis straight; fruiting pedicels ascending, persistent, stout. Sepals oblong or narrowly so, free, caducous, erect to ascending, equal, base of lateral pair not saccate; petals purple, erect with flaring blade, longer than sepals; blade obovate to oblong, obtuse to rounded at apex; claws somewhat differentiated from blade, shorter than sepals, glabrous, unappendaged, entire; stamens 6, slightly exserted, slightly tetradynamous; filaments wingless, unappendaged, glabrous, free; anthers linear, not apiculate; nectar glands lateral, semi-annular, extrastaminal, median glands absent; ovules 30−64 per ovary; placentation parietal. Fruits dehiscent siliques, linear, latiseptate, not inflated, unsegmented; valves thick leathery, with an obscure midvein, glabrous, not keeled, smooth, wingless; gynophore obsolete or to 3 mm; replum rounded, visible; septum complete, hyaline, not veined; style stout, to 3 mm; stigma slightly 2-lobed, lobes not decurrent, opposite replum, unappendaged. Seeds uniseriate, narrowly winged, ovate to broadly oblong, flattened; seeds coat very minutely reticulate, not mucilaginous when wetted; cotyledons accumbent.
One species: Central Asia.