Annual (?); stem slender, unbranched, about 0.9 m tall, sparingly coarse-strigose; leaves opposite to mid-stem, alternate above, narrowly linear-lanceolate, about 6 cm long, 6 mm wide, acute, entire, narrowly attenuate to a sessile base, thinly appressed hispid; head solitary about 1.0 cm across; involucral bracts lanceolate, acute, minutely rough-hairy; rays few, yellow, narrow, about 1.0 cm long; disk flowers with reddish-brown lobes, glabrous, base obscurely pubescent; achenes hairy at the tip with two readily falling scales at the summit. Flowers in September.
Helianthus paradoxus differs in having leaves with less hirsute surfaces and more prominent lateral veins, a branched top, and fewer hairs on the top of the fruit.
New Mexico, Cibola County (?).
Perhaps wet ground based on the collection locality for the only specimen.
None possible until populations are discovered. Additional field searches are needed to determine the range, abundance, habitat, reproduction and other important biological parameters. Taxonomic relationship between Helianthus praetermissus and H. paradoxus needs clarification.
*New Mexico Native Plants Protection Advisory Committee. 1984. A handbook of rare and endemic plants of New Mexico. University of New Mexico Press, Albuquerque.
Heiser, C.B., D.M. Smith, S.B. Clevenger and W.C. Martin. 1969. The North American sunflowers (Helianthus). Memoirs of the Torrey Botanical Club 22(3):1-218.
Sitgreaves, L. 1853. Report of an expedition down the Zuni and Colorado rivers. Senate Executive Document Number 59, 32nd Congress, 2nd Session. Reprinted in 1962 by Rio Grande Press, Chicago, Illinois.
*Watson, E.E. 1928. Contributions to a monograph of the genus Helianthus. Papers of the Michigan Academy of Science, Arts and Letters 9:305-476.