Helianthus devernii
| Helianthus devernii | |
|---|---|
| |
| Side view of the flower | |
Scientific classification 
| |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Asterales |
| Family: | Asteraceae |
| Genus: | Helianthus |
| Species: | H. devernii
|
| Binomial name | |
| Helianthus devernii T.M.Draper
| |
Helianthus devernii is a North American species of flowering plant in the Asteraceae family, known by the common name Red Rock sunflower. It is noted for its small area of distribution—less than 1 square acre.[2]
Taxonomy[edit]
In 2007, a researcher was conducting botanical surveys throughout the Spring Mountains in Nevada. The botanist did not recognize the plant, and it was not possible to use a dichotomous key because the inflorescences were too young. The botanist returned several weeks later when the plant was in a more advance phenology, but was unable to make a positive identification using regional floras. The plant was brought to Dr. Wesley Niles at the University of Nevada, Las Vegas but he, too, failed to make a positive identification. Another collection was sent to Dr. Edward Schilling at the University of Tennessee, who first suggested pursuance of a potentially new species. The first spring, second spring, and third southern cluster cover 800 square meters, 1800 square meters, and 4 square meters, respectively.[2]
As of 2024[update] it is an accepted species according to Plants of the World Online and World Plants,[3][4] but is listed as "unchecked" by World Flora Online.[5]
Distribution and habitat[edit]
The perennial herb is found within and around a small portion of Red Rock Canyon National Conservation Area in Clark County, Nevada[6]—a Bureau of Land Management (BLM)-managed National Conservation Area within the Mojave Desert. Part of the population occupies a named spring, but the majority grow in the riparian area created from well directly north of the spring. The Red Rock sunflower appears to require water in order to grow successfully, although it tends to occupy the dry upland area directly adjacent to the riparian area. The springs are within low-elevation desert scrub.
Original counts put the total number of individuals at around 400.[1] BLM completed dynamic surveying in 2020 and the new total became slightly higher. Once survey methods were established, a new count in 2022 found approximately 900 individuals, which remains the accepted count to this day, as no further surveys have been conducted.
Conservation[edit]
The plant is critically imperiled due of its limited range and the threats in the area,[1] which is a site of recreation, both legal and illegal. The latter includes equestrian use and off-trail hiking. Because of the recreational activities, noxious and invasive weeds are prevalent in the area, including Brassica tournefortii, Salsola tragus, Schismus spp. Invasive animals, like the Burro, also threaten the plant.[citation needed]
A meeting to petition having the plant state-listed as a threatened and endangered species will occur in June 2024. While there are currently mitigation and management strategies underway, the results of this meeting will dictate the future direction for the conservation of the species.[6]
References[edit]
- ^ a b c NatureServe (2024). "Helianthus devernii". Arlington, Virginia. Retrieved 19 June 2024.
- ^ a b Draper, Trent M.; Esque, Todd C. (17 September 2021). "A New Species of Heliantus (Asteraceae) From Clark County, Nevada". Madroño. 68 (1). doi:10.3120/0024-9637-68.1.52.
- ^ "Helianthus devernii T.M.Draper". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 19 June 2024.
- ^ Michael, Hassler (16 June 2024). "Synonymic Checklist and Distribution of the World Flora. Version 19.3". World Plants. Retrieved 19 June 2024.
- ^ "Helianthus devernii T.M.Draper". World Flora Online. Retrieved 19 June 2024.
- ^ a b "NDF to hold Workshop to Update State Protected Flora List". Nevada Division of Forestry. Retrieved 19 June 2024.