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 Species Spotlight

Image of Texas Horned Lizard (Phrynosoma cornutum), courtesy of Texas Parks and Wildlife Department
Photo courtesy of TPWD

Texas Horned Lizard
Phrynosoma cornutum

Description: The Texas horned lizard or "horny toad" is a flat-bodied, spiny, ant-eating lizard. This lizard is brownish with two rows of fringed scales along each side of its body. This species is distinguished from other horned lizards by dark brown stripes that radiate downward from the eyes and across the top of the head.

Life History: They are most active during the warm days of summer and early fall, then hibernate through winter. They spend most of their time either basking in the sun or burrowing. One unique characteristic of the Texas horned lizard is its ability to squirt blood through the eye when threatened.

Habitat: They can be found in arid and semiarid habitats in open areas with sparse plant cover. Because horned lizards dig for hibernation, nesting and insulation purposes, they commonly are found in loose sand or loamy soils.

Distribution: Texas horned lizards range throughout much of Texas, Oklahoma, Kansas, New Mexico, and into northern Mexico.

Status: Threatened, chiefly due to human factors including habitat loss, collection for the pet trade, and the introduction of fire ants.


The Center for Reptile and Amphibian Conservation Mgmt.

Fort Worth Zoo

Texas Parks and Wildlife Dept.

 Arid Lands

Bonamia ovalifolia [Photo: Betty Alex, Big Bend Sensitive Plant Project]
Bonamia ovalifolia [Photo: Betty Alex, Big Bend Sensitive Plant Project]

Sensitive Plants of Big Bend National Park

Big Bend National Park classifies sensitive plants as species that are either very rare or are subject to heavy poaching pressure and are in danger of being extirpated, or eliminated, from the Park. The Park's current list of sensitive plants includes 210 species.

Batesimalva violacea [Photo: Betty Alex, Big Bend Sensitive Plant Project]
Batesimalva violacea
[Photo: Betty Alex, Big Bend Sensitive Plant Project

The Big Bend sensitive plant project focuses on locating sensitive plant species to:

  • document their location within Big Bend National Park,
  • understand the habitat requirements of sensitive plants in the Park,
  • photograph sensitive plant species to assist in preservation efforts in other areas of the Park,
  • and get a general census of the population density of sensitive plant species in  the Park.



Rare Orchids of Big Bend


Image of Hexalectris spicata, courtesy of Betty Alex, Big Bend Sensitive Plant Project
Hexalectris spicata
Image of Hexalectris nitida, courtesy of Betty Alex, Big Bend Sensitive Plant ProjectHexalectris nitida
Image of Hexalectris revoluta, courtesy of Betty Alex, Big Bend Sensitive Plant ProjectHexalectris revoluta
Image of Hexalectris warnockii, courtesy of Betty Alex, Big Bend Sensitive Plant Project
Hexalectris warnockii

[Photos courtesy of Betty Alex, Big Bend Sensitive Plant Project]

  • Hexalectris spicata ranges over the southern US, but occurs infrequently. The species is rare within the Park and is threatened by forest management practices. The Park documented H. spicata var. spicata at one site in large numbers (31 individuals), and H. spicata var. arizonica at four other sites in somewhat lower numbers (40 individuals total).

  • Hexalectris revoluta, the rarest of the Hexalectris species occurring within the Park, is known from three Trans-Pecos mountain ranges, two sites in Arizona and a few sites in Mexico. One of its common names, Chisos Coral Root, reflects the fact that the Chisos Mountains are the best-known location for this species.

  • Hexalectris warnockii, has a very spotty distribution from the Dallas, Texas, area to southern Arizona with wide areas of no occurrence between sites. In 2004, the Park documented 25 plants at six locations, with one large population of 17 plants.

  • Hexalectris nitida, has a spotty distribution across Texas and northern Mexico. In 2004 the Park found the species in five localities, four of which were new locations, with 18 plants.

  • Hexalectris grandiflora, is known only from the Chisos and Davis Mountains of Trans-Pecos Texas and a few sites in the Chihuahuan Desert of Mexico. The Park previously documented only one herbarium record of H. grandiflora, and the single population found in 2004 was at that recorded location.

 Species Spotlight

image of Confused Ladies' Tresses (Deiregyne confusa), courtesy of Big Bend Sensitive Plant Project, Betty Alex
Photo courtesy of Big Bend Sensitive Plant Project, Betty Alex

Confused Ladies' Tresses
Deiregyne confusa


Description: The most exciting single find of 2004 was the orchid species, Deiregyne confusa (Confused Ladies' Tresses), which was last found in the Park and in the United States in 1931. Though several competent botanists had searched for it through the years, no other records of it existed. Staff spotted the Deiregyne confusa and soon a second plant was found relatively close to the first one. The Park is currently in contact with the orchid expert on this species, Dr. Gerardo Salaza

Distribution: The Deiregyne confusa (Confused Ladies' Tresses) is one of four colorful ladies tresses orchids that grow on rocky stream banks in the Trans-Pecos region of Texas. The Deiregyne confusa was collected in 1931 from the Chisos Mountains. The genus Deiregyne consists of fourteen species that are mostly native to Mexico and Guatemala.

Status: The Deiregyne confusa (Confused Ladies' Tresses) is extremely rare. The orchid has up to fifteen pale pink, green-striped flowers that are about 2/3 inch long and pointing downward. The dorsal seapal and two petals form a hood over a green-veined, deeply grooved whitish pink lip. (refer Wild Orchids of Texas, Joe Liggio)

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