72. Noccaea Moench, Suppl. Meth. 89. 1802.
[For Domenico Nocca, 1758-1841, Italian clergyman, botanist, director of botanic garden at Pavia]
Ihsan A. Al-Shehbaz
Biennials or perennials; (stoloniferous or simple or several from caudex); not scapose; (often glaucous). Stems erect or decumbent, unbranched or branched distally. Leaves basal and cauline; petiolate or sessile; basal rosulate, petiolate, margins entire, denticulate, or dentate; cauline blade (base auriculate or subamplexicaul [sagittate]), margins entire or dentate. Racemes (corymbose, several-flowered), considerably elongated or congested in fruit. Fruiting pedicels horizontal or, rarely, ascending, slender. Flowers: sepals erect, oblong, or ovate [obovate]; petals white, pink, or purple, spatulate [obovate, oblanceolate, oblong, or, rarely, broadly linear], (longer than sepals), claw obscurely differentiated from blade, (apex obtuse or rounded); stamens slightly tetradynamous; filaments not dilated basally; anthers ovate [oblong], (apex obtuse); nectar glands lateral, 2 and subtending stamens, or 4 and 1 on each side of stamen. Fruits sessile, obcordate, obovate, obdeltate, elliptical, or oblong, smooth, strongly angustiseptate, (winged or not winged apically); valves each obscurely to prominently veined, strongly keeled; replum rounded; septum complete; ovules 4-14[-24] per ovary; style included in, or much exceeding, apical notch; stigma capitate. Seeds plump or slightly compressed, not winged, ovoid [oblong]; seed coat (longitudinally, minutely reticulate to nearly smooth), not mucilaginous when wetted; cotyledons accumbent. x = 7.
Species ca. 80 (3 in the flora): North America, Mexico, South America (Patagonia), Europe, Asia, n Africa.
SELECTED REFERENCES Holmgren, P. K. 1971. A biosystematic study of North American Thlaspi montanum and its allies. Mem. New York Bot. Gard. 21(2): 1-106. Koch, M. and I. A. Al-Shehbaz. 2004. Taxonomic and phylogenetic evaluation of the American "Thlaspi" species: Identity and relationship to the Eurasian genus Noccaea (Brassicaceae). Syst. Bot. 29: 375-384.