''Hymenothrix loomisii'', the Loomis' thimblehead, is a North American species of flowering plant in the

daisy family Asteraceae () is a large family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the order Asterales. The number of species in Asteraceae is rivaled only by the Orchidaceae, and which is the larger fam ...

. It grows in the southwestern United States (

Arizona Arizona is a U.S. state, state in the Southwestern United States, Southwestern region of the United States, sharing the Four Corners region of the western United States with Colorado, New Mexico, and Utah. It also borders Nevada to the nort ...

New Mexico New Mexico is a state in the Southwestern United States, Southwestern region of the United States. It is one of the Mountain States of the southern Rocky Mountains, sharing the Four Corners region with Utah, Colorado, and Arizona. It also ...

, southern

Nevada Nevada ( ; ) is a landlocked state in the Western United States. It borders Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the seventh-most extensive, th ...

), and also in the

Sierra Madre Occidental The Sierra Madre Occidental is a major mountain range system of the North American Cordillera, that runs northwest–southeast through northwestern and western Mexico, and along the Gulf of California. The Sierra Madre is part of the American C ...

in western Chihuahua. There have been reports of populations in southern California but these are most likely introductions. ''Hymenothrix loomisii'' is an annual herb up to tall. Each head has 10-20 yellow or cream-colored disc flowers but no ray flowers.Flora of North America, ''Hymenothrix loomisii'' S. F. Blake, 1927.
/ref>Blake, Sydney Fay. 1927. Proceedings of the Biological Society of Washington 40(10): 49–50
/ref>

References

Bahieae Flora of Arizona Flora of Chihuahua (state) Flora of Nevada Flora of New Mexico Plants described in 1849 Taxa named by Sidney Fay Blake {{Asteroideae-stub