鼠毛菊 shu mao ju

Scorzonera hemilasia Bunge, Beitr. Fl. Russl. 201. 1852; Epilasia cenopleura (Bunge) C. B. Clarke ex Soják; E. hemilasia var. nana (Boissier & Buhse) Kuntze; E. intermedia (Bunge) C. B. Clarke ex Soják; S. cenopleura Bunge; S. intermedia Bunge; S. nana Boissier & Buhse.

Herbs usually 5-50 cm tall, annual. Stem ascending to erect, unbranched or moderately branched often already from base, arachnoid hairy, glabrescent, basally densely and higher up distantly leafy. Leaves narrowly spatulate or narrowly lanceolate to linear-lanceolate, 2-9 × 0.3-1.5 cm, ± arachnoid hairy, base attenuate and finally semiamplexicaul, margin densely microdentate, apex acute to acuminate. Synflorescence diffuse, paniculiform to corymbiform, with several capitula or more rarely capitulum solitary. Involucre ovoid-cylindric to globose, 1.2-1.4 × 0.8-1 cm at anthesis, 1.5-1.7 × ca. 1.5 cm in fruit (outer phyllaries not counted). Outer phyllaries lanceolate, usually 2-4 cm, herbaceous and similar to upper stem leaves, distinctly longer than inner phyllaries, apex acuminate; inner phyllaries lanceolate, leathery, margin somewhat scarious, apex obtuse to acute. Florets pale yellow, slightly longer than involucre. Achene blackish, cylindric, 6-7 mm, with hollow ± cylindric 1-2 mm carpophore, body in lower half with 10 pale narrow raised often somewhat spinulose ribs, upper half covered and hidden by conic caplike pappus disk and pappus. Pappus gray, 8-10 mm. Fl. and fr. Apr-May. 2n = 12, 24.

Sand or clay areas, grasslands; 800-1500 m. Xinjiang [Afghanistan, Kazakhstan, Pakistan, Tajikistan, Turkmenistan, Uzbekistan; SW Asia].

The unique achene of Epilasia hemilasia is interpreted here through a modification of the pappus disk. Normally the pappus disk is a ± flat disklike (or because of its central opening for the vascular strands connecting achene and floret actually rather ringlike) structure bearing the pappus bristles and crowning the achene apex. In this species, the pappus disk is modified to a caplike structure covering the equally fertile apical half of the achene. This interpretation is supported by the fact that the outer series of plumose pappus bristles arises from the callose ringlike structure in the middle third of the achene (morphologically indistinguishable from the outer series of bristles on the pappus disk of E. acrolasia), while other bristles are basally shortly adnate to and then arise from the unribbed, pale brown surface between the callose ring and the achene apex, and the innermost series of ca. 5 bristles arises at the achene apex. The trichomes covering the surface between the bristles are considered as homologues to those at the base of the bristles in E. acrolasia and to the soft fimbriae of the plumose Scorzonerinae pappus in general.