Lastarriaea
in C. Gay, Fl. Chil. 5: 289. 1851 or 1852.
Herbs, annual; taproot slender. Stems arising directly from the root, prostrate to ascending, solid, not fistulose or disarticulating into ringlike segments, thinly pubescent. Leaves quickly deciduous, basal, rosulate; petiole present; blade linear, margins entire, hirsute. Peduncles absent. Inflorescences terminal, cymose, often uniparous due to suppression of secondaries; branches dichotomous, brittle and disarticulating into segments, round, thinly pubescent; bracts 2, opposite, connate proximally, lanceolate to narrowly ovate, mucronate or awned, thinly pubescent. Involucral bracts obvious, in 1 whorl of 3, linear to broadly lanceolate, awn-tipped. Flowers 1 per involucral cluster; perianth light green to greenish white, cylindric, thinly pubescent abaxially; tepals 5, connate 1/2–3/4 their length, slightly dimorphic, coriaceous, acute and awn-tipped apically; stamens 3; filaments basally adnate, glabrous; anthers cream to white, oval. Achenes mostly included, brownish, not winged, lenticular to slightly 3-gonous, glabrous. Seeds: embryo straight. x = 20.
Distribution
w North America (including Mexico), s South America.
Discussion
Species 3 (1 in the flora).
The awn-tipped, coriaceous tepals easily distinguish Lastarriaea from other genera of the Eriogonoideae. The mostly prostrate habit with brittle stems and inflorescence branches is seen elsewhere in Chorizanthe, most notably C. brevicornu and in the Baja California, Mexico, endemic C. interposita (the only species of sect. Clastoscapa), and because of these features early authors assigned the North and South American species of Lastarriaea to Chorizanthe. The names L. chilensis J. Rémy and C. lastarriaea Parry have been misapplied to the California species.
Selected References
None.