Alyssum lenense Adams

An examination of the holotypes of Alyssum lenense and A. calycocarpum var. edentatum reveals that they are one taxon. The former is highly variable, and some of its many forms were previously recognized as varieties. Alyssum calycocarpum Ruprecht is restricted to the Caucasus and adjacent SW Asia. In fact, the type of var. edentatum is very similar to plants of A. lenense that have persistent sepals and that were described as A. altaicum.

Herbs perennial, cespitose, (3-)7-25(-30) cm tall, often woody at base, canescent throughout with sessile, 7-16-rayed stellate trichomes. Stems usually erect or ascending, often several from caudex, sterile shoots often several. Cauline leaves subsessile; leaf blade linear-lanceolate to linear-oblong, 0.4-2(-3) cm × (0.5-)1-3 mm, gradually smaller upward, base attenuate, apex acute. Racemes corymbose, simple on each stem. Fruiting pedicels divaricate, (3-)4-7(-9) mm, stout, straight, uniformly stellate or sometimes also with simple and forked trichomes. Sepals oblong, 2.5-3 × 1-1.5 mm, deciduous or rarely persistent, stellate. Petals yellow, broadly spatulate, (4.5-)5-7(-8) × (1-)2-3 mm, glabrous outside, caducous, base attenuate, apex rounded or emarginate. Filaments 2.5-4 mm; median pairs slender or slightly flattened above base, neither winged nor toothed; lateral pair with a minute, unilateral tooth just above base; anthers narrowly oblong, 0.7-1 mm. Ovules 2 per locule. Fruit broadly oblong or oblong-obovate, (3-)4-7 × 3-5 mm, apex emarginate and to 0.5 mm deep; valves not veined, 1 inflated, another concave, margin often not flat, glabrous or sparsely stellate; style 1.5-2.8(-3.5) mm, slender, glabrous. Seeds 2 per locule, ovate or oblong, 1.3-2 × 0.9-1.2 mm, compressed, not margined. Fl. May-Jun, fr. Jul-Aug. 2n = 16.

Grassy slopes, forests, sandy places. Gansu, Hebei, Heilongjiang, Nei Mongol, Xinjiang [Kazakhstan, Mongolia, Russia].

Alyssum altaicum C. A. Meyer; A. altaicum var. dasycarpum C. A. Meyer; A. altaicum var. leiocarpum C. A. Meyer; A. calycocarpum Ruprecht var. edentatum H. L. Yang; A. fischerianum de Candolle; A. lenense var. dasycarpum (C. A. Meyer) N. Busch; A. lenense var. leiocarpum (C. A. Meyer) N. Busch.