Arizona Eryngo

The Arizona eryngo (Eryngium sparganophyllum) is an herbaceous flowering plant in the Apiaceae, or carrot, family. This perennial occurs only in spring-fed aridland cienegas, or wetlands, of the International Four Corners Region that includes Arizona, New Mexico and Sonora, Chihuahua. On March 4, 2021, the U.S. Fish and Wildlife Service published a proposed rule to list this species as endangered and designate critical habitat under the Endangered Species Act (86 FR 12563). 

The species is known historically from six sites: 

• Within the United States - Three sites in Arizona and one site in New Mexico 
• Within Mexico – One in Sonora and the other in Chihuahua 

It likely historically occurred at additional cienegas. The plant has been extirpated from two sites: 

• Agua Caliente, Arizona 
• Las Playas, New Mexico 

The species remains extant at four sites: 

• La Cebadilla, Pima County, Arizona 
• Lewis Springs, Cochise County, Arizona 
• Rancho Agua Caliente, Sonora, Mexico 
• Ojo Vareleño, Chihuahua, Mexico 

Population sizes at these sites are highly variable, ranging from approximately 50 to more than 30,000 plants. Efforts are underway to reintroduce the species to the historical site in Arizona from which it was extirpated, known as Agua Caliente, as well as to introduce the species to a new site within its general historical range.

The primary historical threat to Arizona eryngo was physical loss and alteration of cienega habitat. Historically, cienegas were more common and larger than they are today, however, greater than 95% of the historical area of cienegas in the southwestern U.S. and northwestern Mexico is now dry. The primary current threats to Arizona eryngo, a cienega obligate, are water loss due to groundwater withdrawal and water diversion. Additionally, this plant faces threats from an invasion of non-native and woody plant species. Both of these threats are exacerbated by drought and warming caused by climate change climate change
Climate change includes both global warming driven by human-induced emissions of greenhouse gases and the resulting large-scale shifts in weather patterns. Though there have been previous periods of climatic change, since the mid-20th century humans have had an unprecedented impact on Earth's climate system and caused change on a global scale.

Learn more about climate change . These threats reduce the availability of moist soils, and invasive species invasive species
An invasive species is any plant or animal that has spread or been introduced into a new area where they are, or could, cause harm to the environment, economy, or human, animal, or plant health. Their unwelcome presence can destroy ecosystems and cost millions of dollars.

Learn more about invasive species compete for sunlight and space. These actions taken collectively reduce the quantity and quality of habitat for the species.    

Designated critical habitat includes two occupied units in Arizona, which total about 13 acres. The two units include: 

• Lewis Springs, in Cochise County: 9.6 acres (Roughly 3.9 hectares) 
• La Cebadilla, in Pima County: 3.1 acres (1.3 hectares)

To learn more about this species, please see our Species Status Assessment Report for Eryngium sparganophyllum (Arizona Eryngo) and the proposed listing and critical habitat rule (86 FR 12563) in the information and media section of this page.