Sandbergia


Sandbergia is a genus of flowering plants belonging to the family Brassicaceae. They are also in the Boechereae Tribe.

Description

They are biennials or perennial plants. They have a caudex which is simple or branched and covered with persistent leaf remains. It is pubescent throughout. The trichomes have short stalks or are subsessile, cruciform, Y-shaped, or forked. The stems are erect or decumbent, unbranched or branched distally. The leaves are basal or cauline. They are petiolate or sessile. The basal leaves are usually rosulate, petiolate, with the blade margins entire, dentate, or lyrate-pinnatifid with the apex obtuse to acute. The cauline leaves are sessile, with the blade and not auriculate, the margins are entire, subentire, dentate, or pinnatifid. The racemes are ebracteate, and corymbose and several-flowered. They are considerably elongated when in fruit. The fruiting pedicels are ascending to subdivaricate, straight, slender and terete. The flowers have erect sepals which are oblong. It has white petals, which can have a pink tinge or veining, which are oblanceolate-spatulate and longer than sepals. The claw is obscurely differentiated from blade with a rounded apex. The stamens are slightly tetradynamous. The filaments are not dilated basally and slender in form. The anthers are ovate or oblong with an obtuse apex. The nectar glands are confluent and subtending the bases of the stamens. The fruits are subsessile or shortly stipitate. The gynophore is less than 1 mm long, linear, slightly to strongly torulose, subterete to strongly latiseptate. The valves are each without midvein or with obscure one on proximal 1/2. They are sparsely to densely pubescent or glabrescent. The replum is rounded and the septum is complete. It has 12-30 ovules per ovary. The style is obsolete or distinct. The stigma is capitate. The seeds are uniseriate, plump, not winged and oblong shaped. The seed coat is minutely reticulate, not mucilaginous when damp. The cotyledons are incumbent.
It has a chromosome count of x = 7.

Taxonomy

The genus name of Sandbergia is in honour of John Herman Sandberg, a Swedish-born American doctor, botanist and agronomist, who collected many plants in the Pacific northwest of America.
It was first described and published in Leafl. Bot. Observ. Crit. Vol.2 on page 136 in 1911.
The genus is recognized by the United States Department of Agriculture and the Agricultural Research Service, but they do not list any known species.

Known species

As accepted by Plants of the World Online;
  • Sandbergia perplexa
  • ''Sandbergia whitedii''

Distribution and habitat

It is native range is western Canada and north-western U.S.A.
Sandbergia perplexa is found on sparsely vegetated, gravelly slopes of steppes, mountain woodlands, or pine covered woodlands in the montane zone.
While, Sandbergia whitedii is found on dry scabland, gravelly hillsides, dry sandy slopes, alpine meadows, cliffs and on ridge crests. It grows at altitudes of above sea level.