Carnegiea gigantea, Giant Saguaro

Southwest Desert Flora

Home to the plants of the Sonoran, Chihuahuan and Mojave Deserts

Cirsium ochrocentrum, Yellowspine Thistle

Hymenothrix loomisii, Loomis' Thimblehead

Hymenothrix loomisii, Loomis' Thimblehead, Southwest Desert Flora Hymenothrix loomisii, Loomis' Thimblehead, Southwest Desert Flora Hymenothrix loomisii, Loomis' Thimblehead, Southwest Desert Flora    Hymenothrix loomisii, Loomis' Thimblehead, Southwest Desert Flora Hymenothrix loomisii, Loomis' Thimblehead, Southwest Desert Flora    Hymenothrix loomisii, Loomis' Thimblehead, Southwest Desert Flora


Scientific Name: Hymenothrix loomisii
Common Name: Loomis' Thimblehead
Also Called:
Family: Asteraceae, Sunflower Family
Synonyms: ( )
Status: Native
Duration: Annual, biennial or short lived perennial.
Size: Up to 3 feet.
Growth Form: Forb/herb; erect, 1 or more stems from base.
Leaves: Green; alternate, basal leaves with stalks (petioles), upper leaves sessile; simple pinnately divided, linear lobes, glabrous or with short hairs.
Flower Color: Cream, yellow or bright yellow; flower heads small; disk flowers 10-20, corollas creamy to bright yellow outer florets larger, anthers yellow to light brown; flower heads on short stalks (peduncles), less than 3 inches; fruit an achene.
Flowering Season: June to October, summer and fall after monsoon rainfall.
Elevation: 3,500 to 7,000 feet.
Habitat Preferences: Mesas, plains and disturbed sites especially along roadsides.
Recorded Range: Rare in the United States found only in AZ, CA and NV. Also native to northern Mexico. In Arizona it is found in the central, northern and northwestern parts of the state. Marginally found in California and Nevada.

North America & US County Distribution Map for Hymenothrix loomisii.

U.S. Weed Information: No data available.
Invasive/Noxious Weed Information: No data available.
Wetland Indicator: No data available.
Threatened/Endangered Information: No data available.

Genus Information: 3 species in Hymenothrix, all in southwestern United States. All 3 species native to Arizona.

Comments: Loomis’ Thimblehead is similar in appearance to Trans-Pecos Thimblehead, Hymenothrix wislizeni and to Wright's Thimblehead, Hymenothrix wrightii. Clear visible differences between all three in the flowers, Trans-Pecos Thimblehead is the only species with ray flowers, 5 to 8, Loomis’ and Wright's Thimblehead have only discoid flowers. Wright’s Thimblehead has white or pinkish corollas and pinkish anthers and Loomis’ Thimblehead has cream to yellow corollas and anthers.

Date Profile Completed: 8/14/2012, updated: 06/30/2015; Updated, 07/25/2015
References:
Arizona Flora, Kearney, Thomas H., Peebles, Robert H., 1960, University of California Press, Berkley and Los Angeles
The Jepson Manual, Citation: http://ucjeps.berkeley.edu/interchange/I_treat_indexes.html Tue Aug 14 09:16:19 2012
John L. Strother, FNA | Family List | FNA Vol. 21 | Asteraceae | Hymenothrix, Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico. 16+ vols. New York and Oxford. (accessed 08/14/2012)
SEINet for synonyms, scientific names and recorded geographic locations, http://swbiodiversity.org/seinet/