Little Big Bend describes 109 species found in the United States only in Trans-Pecos Texas; 62 of these occur only in the Big Bend portion of the Trans-Pecos, and 24 of them only within Big Bend National Park. Of the 252 featured species, 71 are considered "sensitive plants"; in Texas, 28 are classified as critically imperiled, 18 as imperiled, and 25 as vulnerable. The book features 301 color photographs and a map of the region.