Castilleja halophila
| Castilleja halophila | |
|---|---|
 | |
| Castilleja halophila in bloom | |
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Embryophytes |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Lamiales |
| Family: | Orobanchaceae |
| Genus: | Castilleja |
| Species: | C. halophila |
| Binomial name | |
| Castilleja halophila J.R.Singhurst, J.M.Egger, J.N.Mink & W.C.Holmes | |
Castilleja halophila, commonly known as salt prairie paintbrush or Texas seaside paintbrush, is a species of flowering plant in the family Orobanchaceae. It is endemic to coastal Texas, where it occurs on barrier islands in specialized saline habitats.[2]
Description
Castilleja halophila is a hemiparasitic herbaceous plant characterized by a relatively strict, often unbranched growth habit, typically reaching 45–74 cm in height. The inflorescences bear pale to white bracts, sometimes tinged with pink, surrounding inconspicuous flowers. Like other species of Castilleja, it obtains water and nutrients in part from host plants, particularly salt-tolerant species of Iva.[1]
Taxonomy
The species was described by J.R. Singhurst, J.M. Egger, J.N. Mink, and W.C. Holmes in 2020 in Phytologia (volume 102, issue 3, page 209), published 21 September 2020.[3][4] It is recognized as a distinct species with no widely accepted synonyms.[2]
The species is considered a local derivative of Castilleja indivisa and differs in its earlier flowering period, pale bract coloration, and restriction to saline habitats, with the two species largely parapatric in distribution.[1]
Etymology
The specific epithet halophila is derived from Greek, meaning “salt-loving,” in reference to the species’ occurrence in hypersaline coastal environments.[3]
Distribution and habitat
Castilleja halophila is endemic to the middle Gulf Coast of Texas, where it is known from Nueces, San Patricio, and Aransas counties.[2][1] It occurs on barrier islands and adjacent coastal areas, including sites such as Stedman Island and Harbor Island.[1]
The species inhabits saline to hypersaline soils in coastal prairie-like areas, often within shrubland and herbaceous communities dominated by species such as Borrichia frutescens, Spartina spartinae, and Monanthochloe littoralis.[1]
Phenology
Flowering occurs from January to April, occasionally extending into early June.[2][1]
Ecology
Castilleja halophila is a hemiparasitic annual that relies on host plants for part of its nutrient and water uptake, particularly species of Iva adapted to saline environments.[2][1] It is tolerant of hypersaline soils but appears unable to compete with related species such as Castilleja indivisa in less saline habitats.[1]
Conservation
Castilleja halophila is considered critically imperiled, with a global conservation rank of G1 assigned by NatureServe.[1] It has a highly restricted range of less than 100 km2 and is known from only one to a few occurrences along the Texas coast.[1]
The total population is estimated at 1,000 to 2,500 individuals, with about 1,275 individuals documented in 2020.[1] The species is threatened by sea level rise, maritime industrial activity, dredging, recreational use of coastal waterways, and associated development, all of which contribute to habitat loss and degradation.[1]
Because of its extremely limited distribution and exposure to ongoing coastal threats, the species is considered highly vulnerable to extinction without active conservation management.
References
- 1 2 3 4 5 6 7 8 9 10 11 12 13 "Castilleja halophila". NatureServe Explorer. Retrieved 17 April 2026.
- 1 2 3 4 5 "Castilleja halophila". Flora of the Southeastern United States. Retrieved 17 April 2026.
- 1 2 "Castilleja halophila Singhurst, J.M.Egger, Mink & W.C.Holmes". International Plant Names Index. Retrieved 17 April 2026.
- ↑ "Castilleja halophila". GBIF. Retrieved 17 April 2026.