4. Lachnocaulon engleri Ruhland in H. G. A. Engler, Das Pflanzenreich. 13[IV,30]: 241. 1903.
Herbs, short-lived perennial, solitary or cespitose, forming low domes of rosettes, 6--15 cm. Leaves mostly linear-triangular, 2--4 cm, apex acute. Inflorescences: scape sheaths shorter than or as long as principal leaves; scapes filiform, distally 0.4 mm thick, 4--5-ribbed, glabrous; mature heads dark brown or reddish brown, nearly globose, usually short cylindric by seeding time, 3--4 mm; receptacle densely pilose; involucral bracts soon reflexed, brown, mostly ovate, 1(--1.5) mm, apex broadly acute to obtuse, surfaces glabrous or apex sparsely pilose, hairs translucent, club-shaped; receptacular bracts, dark brown, broadly spatulate or obovate-cuneate, concave, with broad, low, pale keel, 1--1.5 mm, apex short-acuminate, glabrous or abaxial surface with translucent, club-shaped hairs distally. Staminate flowers: sepals 3, dark brown, narrowly spatulate to oblanceolate-cuneate, concave, 1 mm, glabrous or abaxially with scattered translucent, club-shaped hairs distally; androphore pale, narrowly obconic, as long as sepals, glabrous, rarely apex with few club-shaped hairs; stamens 2--3, appendages (2--)3. Pistillate flowers: sepals 3, dark brown, spatulate-oblong, concave, 1 mm, abaxially sparsely pubescent distally, hairs translucent; gynoecium 3-carpellate; styles: apex 3-cleft, appendages 3. Seeds rich translucent brown, broadly ovoid to ellipsoid, 0.4--0.5 mm, longitudinal ribs conspicuous and pale, transverse striae fine forming linear cancellae.
Flowering summer--fall. Moist sandy-peaty lake and pond shores, drawdowns, ditchbanks, low sandy clearings in savanna and flatwoods; of conservation concern; 0--100 m; Ala., Fla.