Ayenia limitaris had previously been reported from Cameron and Hidalgo counties in Texas and in the states of Coahuila and Tamaulipas in Mexico. Texas Ayenia has not been relocated at any of the historic Cameron County locations since the early 1960s.  In the U.S., Texas Ayenia is known from a single locality in Hidalgo County.  Recently, we have learned that more than 20 individuals occupy the site. The species also occurs in the state of Tamaulipas in Mexico.

    Texas Ayenia occurs at low elevations in dense subtropical woodland communities.  It is found on terraces and flood plains, and may be dependent on flooding for nutrient deposition and seed dispersal. However, little is known about the reproductive biology of the species.  Previous collectors have found the plant in openings within chaparral and along the edges of thickets.

    Habitat loss is thought to be the major threat to the continued existence of this species.  Flood control is extremely important to the survival of the species and its ecosystem.  Introduction and spread of non-native species such as guineagrass (Panicum maximum) poses a serious threat.  Moreover, the small size of the existing U.S. population makes this species very vulnerable.