This species ranges from the Gulf Coastal Plain, from south of the San Antonio River in Texas, USA, southward along the Atlantic versant to Tamaulipas, northern Veracruz and south-eastern San Luis Potosi, Mexico. It has never been found more than 130km inland. It occurs from sea level up to 800m asl. Many historical occurrences are no longer extant. The USFWS survey in the mid-1980s reported five localities, two in Texas and three in Mexico, of 221 surveyed. The localities in Mexico are few and far between, and it now seems to be absent from two of the three known localities in Mexico. It still exists in Siberia in northern Veracruz.
Habitat and Ecology
Adults, juveniles, and larvae inhabit permanent and temporary ponds, roadside ditches, and quiet stream pools, habitats that are relatively uncommon in at least the northern part of the range. It is usually found among submerged vegetation, and it is found under rocks and other shelter when ponds dry up. The eggs are attached to submerged vegetation in shallow water (Garrett and Barker 1987). The species is generally intolerant of habitat disturbance except that it has been found in ditches along railroad rights-of-way.
The species has never been found to be abundant at any locality. A maximum of 25 individuals has been found at one site. It was once rather common in Texas, but is now seldom seen (Bartlett and Bartlett 1999). It is apparently still declining in Texas (Bartlett and Bartlett 1999), but much of the range includes private land where herpetological surveys have not been conducted. The populations of this species in Mexico also seem to be very small and declining, but more fieldwork is needed to verify the status of the species in the country.
Extensive habitat alteration for agriculture and infrastructure development in Texas and north-eastern Mexico has had a severe impact on this newt. It has also become endangered in Texas due to insecticide and herbicide use (Dixon 1987), and water pollution is also a major problem in Mexico.
It is not known to occur in any protected areas in Mexico, but these are needed where the species is still found to survive. The species has been reported from the Laguna Atascosa and Santa Ana National Wildlife Refuges, and from the Audubon Sabal Palm Grove Sanctuary in Texas, and may occur in other protected areas. This species is listed as threatened by the Texas Parks and Wildlife Department and endangered by the Mexican government. Research is needed on its demography, the water quality requirements of aquatic stages, what its terrestrial habitat requirements are, and its diet. Potential habitat needs to be surveyed for specimens at optimal times of the year (early spring or after rains).
Flores-Villela, O., Parra-Olea, G., Hammerson, G.A., Wake, D. & Irwin, K. 2008. Notophthalmus meridionalis. In: IUCN 2014