Annuals, 10-50(-150+) cm (some-times branched from bases). Leaf blades: bases obscurely, if at all, clasping, faces sparsely hirtellous to villous (at least on margins, hairs multicellular) and stipitate- to sessile-glandular; proximal ovate to spatulate, 20-50+ × 10-20+ mm, mostly 1-2-pinnately lobed (lobes oblong-linear to filiform); distal similar, pinnately lobed or entire (then linear to filiform). Heads in racemiform or paniculiform arrays (on main and lateral stems). Involucres 2.5-3.5 mm. Receptacles 1.5-2 mm diam. Pistillate florets 20-40+; corollas: lengths ± ¹ / 2 styles, laminae 0. Disc florets 2-6. Cypselae pale pinkish tan, 0.6-0.8 mm, glabrous or sparsely strigillose (hairs 0.05-0.1 mm), sometimes glandular near apices; pappi fragile or readily falling, of 9-12(-20) white to tawny bristles in 1 series, 2-3 mm. 2n = 18.

Flowering late summer-early fall. Disturbed sites, among igneous rocks; 1300-2100 m; Ariz., N.Mex., Tex.; Mexico.

Duration: Annual

Nativity: Native

Lifeform: Forb/Herb

General: Annual herb, forming densely hairy basal rosette; stems 10-100 cm tall, glandular hairs all over plant, hairs resembling spider web; taproot.

Leaves: Leaves 1-3.5 cm long and once or twice pinnately parted into linear lobes.

Flowers: Corollas of the pistillate flowers are tubular-filiform, without a ligule, only about 3 mm high.

Fruits: Cypselae glabrous and puncticulate in fine lines.

Ecology: Found on arid hills, mesas, and plains; 2,500-6,000 ft (762-1829 m); flowers August-October.

Distribution: s AZ, sw NM, TX; south through MEX and in S. America.

Notes: Distinguished by being a densely-sticky glandular annual with small white heads (smaller than L. coulteri), deeply lobed leaves which are barely, if at all, clasping and sparsely hairy but dense with glands (clasping, toothed and densely hairy in coulteri).

Ethnobotany: Unknown

Etymology: Laennecia is named for Rene Theophile Hyancinthe Laennec (1781-1826), while sophiifolia is of uncertain origin.

Synonyms: Conyza sophiifolia

Editor: SBuckley 2010, FSCoburn 2014