Oreocarya crassipes

Oreocarya crassipes
Conservation status
Critically Imperiled  (NatureServe) [1]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Asterids
Order:	Boraginales
Family:	Boraginaceae
Genus:	Oreocarya
Species:	O. crassipes
Binomial name
Oreocarya crassipes (I.M.Johnst.) Hasenstab & M.G.Simpson
Synonyms [2]
Cryptantha crassipesI.M.Johnst.

Oreocarya crassipes is a rare species of flowering plant in the borage family known by the common name Terlingua Creek cat's-eye. It is endemic to Brewster County, Texas, where it is known from only ten populations totaling about 5000 plants. ^[3] All of the occurrences are within a ten-kilometer radius. ^[1] This is a federally listed endangered species.

Description

This is a perennial herb producing several erect stems reaching a maximum height around 25 centimeters. There is a clump of basal leaves around the stem bases. The herbage is covered in silvery soft and bristly hairs. The inflorescence is a head of yellow-throated white flowers. ^[1] The plants are often coated in a sooty black fungus. ^[3]

Distribution and habitat

This plant grows only on the Fizzle Flat lentil, a small geologic formation in the Terlingua Creek watershed just north of Big Bend National Park. ^{[3] [4]} This lentil is a unique expanse of limestone rock which is rich in gypsum and bound with clay. The formation, which locals call a "moonscape", ^[4] is pale yellow in color because of its mineral makeup and about 50 feet thick. ^[5] The chalky rock breaks into plates and contains many fossils. The area is very dry and it receives full, hot sunlight. ^{[3] [1] [6]} The lentil is almost totally devoid of plant life; this species and other hardy plants, such as Castilleja elongata and Lycium berberioides , occur around the edge of the lentil. ^{[3] [1]}

The rare plant is limited to a specific substrate. The area is affected by human activity in several ways. The land is all privately owned and unprotected. Off-road vehicles drive on the badlands, which are used both in the mining of bentonite and for access in the grazing of livestock in the area. ^{[3] [1]}

References

1. Cryptantha crassipes. The Nature Conservancy.
2. "Oreocarya crassipes (I.M.Johnst.) Hasenstab & M.G.Simpson". Plants of the World Online. Royal Botanic Gardens, Kew. 2023. Retrieved 17 April 2023.
3. Cryptantha crassipes. Archived 2010-12-15 at the Wayback Machine Center for Plant Conservation.
4. Cryptantha crassipes. Texas Parks and Wildlife.
5. USGS. Geologic Unit: Fizzle Flat. National Geologic Map Database.
6. USFWS. Final rule to list the plant Cryptantha crassipes (Terlingua Creek Cat's-eye) as endangered. Federal Register September 30, 1991.

External links

• USDA Plants Profile

Further reading

• Moon, C. G. (1953). Geology of Agua Fria Quadrangle, Brewster County, Texas. Geological Bulletin 64:2 151.