DESCRIPTION 



The Texas blind salamander is all white or 

 pinkish with blood-red external gills and tooth- 

 pick-like legs. Head and snout are strongly flat- 

 tened with two small black dots representing 

 vestigial eyes beneath the skin. It reaches a total 

 length of 13 cm. Color photographs appear in 

 Mohr and Poulson (1966), Zahl (1972), and 

 Conant (1975). 



RANGE 



The species occurs only in subterranean 

 waters of the Edwards Aquifer near San Marcos, 

 Hays County, Texas. It can be seen only in caves, 

 sinkholes, and fissures, including Ezell's Cave, 

 Primer's Well, and Rattlesnake Cave. Two addi- 

 tional sites, Johnson's Well and Wonder (Beaver) 

 Cave, have been recorded, but no Texas blind 

 salamanders have been seen in either location for 

 many years (Russell 1976). Longley (1978) has 

 placed nylon nets over Pipe Spring at San Marcos 

 Springs and the type locality artesian well, Aqua- 

 tic Station, Southwest Texas State University in 

 San Marcos, and collected Texas blind salaman- 

 ders as they were washed out of the aquifer. 



Their total distribution is limited to about 

 104 km? mostly beneath the city of San Marcos 

 (Russell 1876). However, based on known distri- 

 bution (see range map), the figure could be less 

 than this, perhaps as little as 10 km^ (F. E. Potter 

 personal communication). 



RANGE MAP 



Current localities (observed within the past 5 

 years) are indicated by dots. Former localities 

 (not observed within the past 50 years) are shown 

 by triangles (F. E. Potter personal communica- 

 tion). 



STATES/COUNTIES 



Texas Hays. 



HABITAT 



The blind salamander inhabits water-filled 

 caverns of the San Marcos Pool of the Edwards 

 Aquifer. It is knovm only from incidental speci- 

 mens washed out of the aquifer or found near the 

 water surface in caves. Water quality is considered 

 very good with average temperatures in the vicini- 

 ty of 21° C (Longley 1978). 



FOOD AND FORAGING BEHAVIOR 



These salamanders feed on any living inverte- 

 brates they can handle, including a tiny snail 

 species, copepods, amphipods, and a shrimp. Cap- 

 tive specimens have been maintained for up to 2 

 years on epigeal forms of daphnia and other small 

 crustaceans, suggesting use of any such forms as 

 may happen to wash into the aquifer from the 

 surface. 



SHELTER REQUIREMENTS 



Not known. 



NESTING OR BEDDING 



Not known. 



RITUAL REQUIREMENTS 



Not known. 



OTHER CRITICAL ENVIRONMENTAL 

 REQUIREMENTS 



The blind salamander is completely adapted 

 to the cave environment. 



POPULATION NUMBERS AND TRENDS 



Information is lacking on population size, but 

 it is believed to be stable because of the large 

 number of specimens and high percentage of ju- 

 veniles washed out of the aquifer by springs and 

 artesian wells. In the 2-year period 1975-1977, 

 Longley (1978) netted 133 specimens, 32 of 

 which washed from the type locality artesian well 

 and 101 of which washed from Pipe Spring at San 

 Marcos Springs, a previously unreported locality 

 for the species. 



REPRODUCTION 



Information on reproduction is scanty. One 

 gravid female contained 39 eggs. Tiny specimens 

 less than 2 cm long have been found throughout 

 the year (Longley 1978). Dunn (1926) reported 

 eggs laid March 15, 1886, and spermatheca 

 packed with spermatozoa in early fall of 1916. 

 Gravid females have been observed each month of 

 the year (F. E. Potter personal communication). 

 Brandon (1971) discusses tesdcular lobes ranging 

 from zero to four in the seven specimens he ex- 

 amined. There appears to be a correlation be- 

 tween size (age class), number of lobes, and num- 

 ber of times sperm has been produced. 



