In Texas, plant species of conservation concern may be listed as threatened or endangered under the authority of state law and/or under the U.S. Endangered Species Act (ESA). Species may be listed as state threatened or endangered and not federally listed. The state list only addresses the status of a species within Texas. The federal list addresses the status of a species throughout all or a significant portion of its range, which may encompass several other states or nations.
Candidate species are those organisms the U.S. Fish and Wildlife Service has sufficient information on to propose as endangered or threatened under the ESA but development of a proposed listing regulation is precluded by other higher priority listing activities. Unlike species listed under the ESA, candidates receive no statutory protection.