(DRAFT) - Taxonomy
                          Species SALAMANDER, BLIND, TEXAS
                                Species Id ESIS202002
                                   Date 14 MAR 96



TAXONOMY

NAME - SALAMANDER, BLIND, TEXAS OTHER COMMON NAMES - SALAMANDER, BLIND and TEXAS ELEMENT CODE - CATEGORY - Amphibians PHYLUM AND SUBPHYLUM - CHORDATA, CLASS AND SUBCLASS - AMPHIBIA, ORDER AND SUBORDER - CAUDATA, FAMILY AND SUBFAMILY - PLETHODONTIDAE, GENUS AND SUBGENUS - TYPHLOMOLGE, SPECIES AND SSP - RATHBUNI, SCIENTIFIC NAME - TYPHLOMOLGE RATHBUNI AUTHORITY - TAXONOMY REFERENCES - COMMENTS ON TAXONOMY - Texas Blind Salamander Typhlomolge rathbuni Stejneger, 1896 KINGDOM: Animal GROUP: Amphibian PHYLUM: Chordata CLASS: Amphibia ORDER: Caudata FAMILY: Plethodontidae The following description is from Stejneger (01): "Head excessively large and broad, the distance from tip of snout to base of upper gill-branch slightly less than distance between axilla and groin, its width equal to one half the latter distance; snout very much depressed, broad, truncated, nearly square anteriorly; nostrils widely separated at the corners of the truncated snout, their distance greater than that between the eyes, which are deeply hidden under the skin and only visible as two dark spots; mouth comparatively small, with strongly developed labial lobes; body short and slender, the distance between axilla and groin being slightly greater than the length of head and only half the length of the tail, its width being much less than that of the snout; limbs excessively slender and long, of nearly even length, about one-fifth of the total length; fingers over-lapping knee and Taxonomy - 1 (DRAFT) - Taxonomy Species SALAMANDER, BLIND, TEXAS Species Id ESIS202002 Date 14 MAR 96 toes overlapping elbow when adpressed to the sides of the body; fingers four, toes five, short, slender, free, with rounded tips, their relative length variable; tail comparatively long, nearly one-half the total length, much compressed, finned below and particularly strongly above, the end pointed." Skin smooth; a very strongly marked gular fold; a well marked vertebral groove; eleven costal groves. Teeth on intermaxillaries and mandible small; the vomero-palatine teeth large, decreasing in size at both ends. Gill branches long and slender, the middle one longer; fimbriae long and slender, not bushy. Color nearly white, semi-transparent, the upper surfaces densely sprinkled with minute pale gray dots. Dimensions (mm) - Total length 102; from snout to anus, 53; from snout to gular fold, 16; from snout to beginning of upper gill branch, 22; width of head, 13; width of snout, 9; distance between nostrils, 7; distance between eyes, 6; distance between axilla and groin, 25; fore limb, 20; hind limb, 20; longest finger, 2 2.3; longest toe, 2.5; width of limbs, 1.7 (11). Stejneger (01) was the first to describe the blind salamander, Typhlomolge rathbuni, from specimens in the U.S. National Museum. The type specimen from which the species was described is No. 22686 USNM. Emerson (02) described the general anatomy of this species and Eigenmann (03) described what he termed degenerative evolution. Hilton (04) described the skeletal structure of the blind salamander, and Dundee (05) described induced partial metamorphosis. In 1965 Mitchell and Reddell (06) proposed the removal of Typhlomolge to the genus Eurycea. Wake (07) stated that both Eurycea and Typhlomolge developed from the same ancestor, a Pro-Eurycea and, for this reason suggested retention of the genus Typhlomolge. Brandon (08,09,10) also supported retention of Typhlomolge. Clerque-Gazeau (11), however, used the genus Eurycea. Potter and Sweet (13) in 1981 have stated that existing morphological evidence is inadequate to resolve the status of the genus Typhlomolge. Taxonomy - 2
                                  (DRAFT) - Status
                          Species SALAMANDER, BLIND, TEXAS
                                Species Id ESIS202002
                                   Date 14 MAR 96



STATUS

Coded Status E: Federal Endangered COMMENTS ON STATUS - U.S. STATUSES AND LAWS: The Texas blind salamander (Typhlomolge rathbuni) has been designated an Endangered species pursuant to the Endangered Species Act of 1973 (50 CFR 17.11; P.L. 93-205, 87 Stat. 884; 16 U.S.C. 1531-1540), as amended. The species has this status wherever found, including the State of Texas. This species is protected by the Lacey Act (P.L. 97-79, as amended; 16 U.S.C. 3371 et seq.) which makes it unlawful to import, export, transport, sell, receive, acquire, or purchase any wild animal (alive or dead including parts, products, eggs, or offspring): (1) in interstate or foreign commerce if taken, possessed, transported or sold in violation of any State law or regulation, or foreign law; or (2) if taken or possessed in violation of any U.S. law, treaty, or regulation or in violation of Indian tribal law. It is also unlawful to possess any wild animal (alive or dead including parts, products, eggs, and offspring) within the U.S. territorial or special maritime jurisdiction (as defined in 18 U.S.C. 7) that is taken, possessed, transported, or sold in violation of any State law or regulation, foreign law, or Indian tribal law. RESPONSIBLE FEDERAL AGENCIES: USFWS -Responsible for the management/recovery, listing, and law enforcement/protection of this species. All Federal agencies have responsibility to ensure that any action authorized, funded, or carried out by that agency is not likely to jeopardize the continued existence of the species or result in the destruction or adverse modification of Critical Habitat (50 CFR 402), and to utilize their authorities to carry out programs for the conservation of the species. STATE STATUSES AND LAWS: STATE: Texas DESIGNATED STATUS: Endangered ADMINISTRATIVE AGENCY: Texas Parks and Wildlife Department STATE STATUTE: Texas Parks and Wildlife Code, Sec. 43, 67, Status - 1 (DRAFT) - Status Species SALAMANDER, BLIND, TEXAS Species Id ESIS202002 Date 14 MAR 96 and 68. INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS: The Texas blind salamander is listed as Endangered by the U.S. in the Western Hemisphere Convention Annex (1970). ECONOMIC STATUSES: This species has value as a component of Texas's natural heritage of biological diversity. 67/03/11:32 FR 40001/ - Listed as Endangered 79/05/21:44 FR 29566/29577 - Status review 85/07/22:50 FR 29901/29909 - 5-year review Status - 2
     

HABITAT ASSOCIATIONS

HABITAT - AQUATIC INLAND AQUATIC LAND USE - Mixed Urban or Built-up Land Herbaceous Rangeland Streams and Canals NATIONAL WETLAND INVENTORY CODES NWI NWICLS NWIMOD NWISPEC Riverine, intermittent UB Riverine, intermittent RB2 Riverine, intermittent RB1 Riverine, intermittent OW0 Riverine, upper perennial RB2 Riverine, upper perennial RB1 Riverine, upper perennial OW0 COMMENTS ON HABITAT ASSOCIATIONS - The Texas blind salamander is aquatic throughout life, living in interconnected, water-filled cavernous areas in the San Marcos pool of the Edwards Aquifer, Hays County, Texas. The salamander travels along ledges and occassionally swims in deep pools, then settling to the bottom (11,12). Longley (11) reports this species from Johnson's Well, Primer's Fissure, Ezell's Cave, Wonder Cave, an unnamed artesian well, San Marcos Spring, Rattlesnake Cave (developed on the edge of two collapsed sinks) (12, 14). These sites represent a stretch of about four kilometers known as the San Marcos Pool at the northern end of the Edward's Aquifer. According to Longley (11) this salamander is probably restricted to an area of about 10,342 hectares most of which is located directly below the city of San Marcos, Texas. The San Marcos area lies along the edge of the coastal plain between Austin and San Antonio, Texas. Two miles north of San Marcos, the Blanco River flows from the Edwards Plateau and connects to the San Marcos River which emanates from the San Marcos Springs, now developed into a tourist attraction. Two smaller streams (normally dry), Sink Creek and Purgatory Creek, form wide valleys extending to the north and along the south of San Marcos. Johnson's Well and Primer's Fissure (Well) are in the Purgatory Creek channel (12). Elevations in the San Marcos area range from 550 feet to 1000 feet in the hills west of San Marcos. The area receives about 33 inches of rain per year (which varies widely) and has an average temperature of 68 deg. F (12). Sissom and Davis (14) have measured some of the chemical and physical parameters of Ezell's Cave. Water temperature varied from a low of 21 deg. C to a high of 22 deg. C with a yearly average of 21.4 deg. C. Dissolved oxygen ranged from 4.42 mg/l to 4.96 mg/l with an average of 4.70 mg/l. Phenolpthalein alkalinity was constantly zero throughout the study period. Methyl orange alkalinity ranged from 236 mg CaCOs/l to 257 mg CaCOO3/l with a yearly average of 249 mg CaCO3/l; pH increased from a low of 6.9 in July of 1978 to a high of 7.4 in July 1979. Free CO2 decreased from a high of 52 mg/l in July of 1978 to a low of 19 mg/l in July of 1979. Nitrates varied from a low of 2.5 mg NO3-N/l to a high of 4.4 mg NO3-N/l with an average of 3.36 mg NO3-N/l. Nitrite Habitat Associations - 1 nitrogen averaged 0.024 mg NO2-N/l and 0.022 mg NO2-N/l. Organic nitrogen, measured by the Kjedahl method, averaged 0.013 mg N/l. Total phosphorous increased from 10 mg P/l in July 1978 to 50 mg P/l in January 1979. Sulfate averaged 31.4 mg/l and chloride values varied less than 2 mg/l. Magnesium averaged 16.2 mg/l and iron averaged 0.016 mg/l. Calcium averaged 109 mg/l. Water level varied with rainfall. For example, water level rose 13 cm following a rainfall of 8.5 cm. Water was usually turbid and contained epigean organism following these abrupt heavy rains. Surface lands are primarily mixed urban development, and herbaceous rangeland. Habitat Associations - 2
                                (DRAFT) - Food Habits
                          Species SALAMANDER, BLIND, TEXAS
                                Species Id ESIS202002
                                   Date 14 MAR 96



FOOD HABITS

TROPHIC LEVEL - CARNIVORE LIFESTAGE FOOD FOOD PART General Zooplankton General Crustaceans General Molluscs Food Habits - 1
                         (DRAFT) - Environment Associations
                          Species SALAMANDER, BLIND, TEXAS
                                Species Id ESIS202002
                                   Date 14 MAR 96



ENVIRONMENTAL ASSOCIATIONS

G = General A = Adult LIM = Limiting RA = Resting Adult J = Juvenile FA = Feeding Adult RJ = Resting Juvenile BA = Breeding Adult FJ = Feeding Juvenile P = Pupae L = Larvae E = Egg RL = Resting Larvae FL = Feeding Larvae
LIFESTAGE ENVIRONMENTAL ASSOCIATIONS G Aquatic Features: Springs [flowing] G Aquatic Features: Pool areas G Terrestrial Features: Caves, wet G G Terrestrial Features: Depressions Environment Associations - 1
                               (DRAFT) - Life History
                          Species SALAMANDER, BLIND, TEXAS
                                Species Id ESIS202002
                                   Date 14 MAR 96



LIFE HISTORY

FOOD HABITS: According to Longley (11) both juvenile and adult blind salamanders feed on any small organism with which they come into contact. The blind shrimp (Palaemonetes antorum) and the larger amphipods are the primary food of larger blind salamanders while young salamanders feed on copepods. Both young and older salamanders feed on hydrobiid snails. Longley (11) notes that the salamanders search for prey with lateral movements of the head. Observations in Ezell's Cave, Primer's Well, and Rattlesnake Cave, indicate the salamanders are quite active, frequently swimming in open water, and spend most of the time searching for food along walls and floors, and in crevices around rocks (12). These large voids tend to concentrate organic food materials. The specialized method of hunting prey involves gliding slowly through the water, probing nooks and cracks. When the prey is disturbed by the snout, the salamander senses movement, quickly opens its mouth, and sucks the prey inside where it is impaled on the needle-like teeth (12). The wide mouth, an adaptation by natural selection, facilitates capture of prey. Quiet water is apparently necessary for this type of hunting technique since water current might inhibit the detection and capture of prey (12). In aquaria with rapid aeration they have no problem finding prey (and current is considerable there) (16). HOME RANGE/TERRITORY: No information exists on home range or territoriality for the Texas blind salamander. PERIODICITY: Studies by Longley have not given any indication of periodicity (16). MIGRATION PATTERNS: No information exists on migration patterns of the Texas blind salamander. COVER/SHELTER REQUIREMENTS: Longley (11) noted that this salamander is especially susceptible to predation when it leaves its cave environments (i.e. is expelled from the spring openings into the surface waters). REPRODUCTIVE SITE REQUIREMENTS: Longley (11) indicated that very little is known about reproductive activity of the the Texas blind salamander including reproductive site requirements. Eggs are laid individually on substrate and airstones in aquaira (16). REPRODUCTIVE CHARACTERISTICS: Longley (11) states that reproduction within this species may be similar to that of other Eurycea. If this is the case the male will deposit several spermatophores which are then picked up by the female Life History - 1 (DRAFT) - Life History Species SALAMANDER, BLIND, TEXAS Species Id ESIS202002 Date 14 MAR 96 with the lips of her cloaca. The gelatinous cap of the spermatophore is then dissolved in the cloaca and the sperm migrates to the female spermatheca. Age at sexual maturity has not been determined. In addition, it is very difficult to sex animals less than 3 cm long. Based on the capture of juveniles throughout the year, reproduction appears to take place year-round. David M. Seven from St. Marys's College, Notre Dame, Indiana, has related to me that the sexas may be distinguised quickly by anesthetizing them (dilute ether) and spreading the cloacal lips slightly with watchmaker forceps (females - dark pigment patch (representing the spermatheca) is visable) (males - have an unpigmented cloaca). Dave Bechler at Lamar University in Beaumont, Texas, has observed a female picking up a spermatophore that had been deposited on the floor of an aquarium. Bechler also observed mating behavior of tail wagging prior to this activity (Longley has also observed this same activity). Work by Maruska at the Cinicinati Zoo has led to the production of numerous offspring. In three different females the following numbers of eggs were deposited: DATE: # of EGGS: 12/10/79 19 eggs deposited hatched in 27-35 days (hatchlings <10 mm) 1/5-6/80 8 eggs deposited 10/24/80 21 eggs deposited hatched in 19-33 days (in 20-21 deg. C) Eggs are variable in size 3.3 x 5.0 mm to 5.0 x 5.9 mm. When hatchlings are fed newly hatched brine shrimp they grow rapidly. Maruska has been able to get reproduction from 2nd generation salamanders that he reared from the original six he had in 1979. (16) PARENTAL CARE: There is little information on the reproductive behavior of this species but, based on observations from studies of congeners, there is little likelihood of any parental care. POPULATION BIOLOGY: Longley (11) made population estimates based on the assumption that a random number of this species were being ejected from springs. Longley estimated that 13 salamanders were ejected from San Marcos Springs each day or 4,745 a year. This is indicative of a very large subterranean population. SPECIES INTERRELATIONSHIPS: In their study of Ezell's Cave, Sissom and Davis (14) found the Texas blind salamander in association with organisms representing 5 phyla, 12 classes, 40 orders, 73 families, 90 genera, and 76 species. These species include a 1 turbellarian, 4 gastropods, 1 oligochaete, 6 crustaceans, 4 diploids, 1 chilopod, 10 arachnids, 23 insects, 1 osteichthys, 3 amphibians, 1 reptile, and 4 mammals. In addition, these species were composed of 34 accidental, 25 trogloxenes, 22 troglophiles, 16 troglobites, and 1 orach of unknown status. Life History - 2 (DRAFT) - Life History Species SALAMANDER, BLIND, TEXAS Species Id ESIS202002 Date 14 MAR 96 Internal parasites found in the salamander include Capillaria sp. (eggs in feces), Hexamita sp. (in gut), Neoechinorhynchus (cylindratus?) (gravid females in gut and bo cavities (Acanthocephala), and digenetic trematode (with eggs in gut) (11). In subterranian habitats T. rathbuni is the top predator. However, when it is brought to the surface (via pumping), it is easy prey for sunfish, and other fish and nekton (11). OTHER LIFE HISTORY DESCRIPTORS: No information exists on other life history descriptors. Life History - 3
                           (DRAFT) - Management Practices
                          Species SALAMANDER, BLIND, TEXAS
                                Species Id ESIS202002
                                   Date 14 MAR 96



MANAGEMENT PRACTICES

RESULT MANAGEMENT PRACTICE Beneficial Restricting/regulating human disturbance of populations Beneficial Controlling water levels Beneficial Controlling pollution [thermal, chemical, physical] Beneficial Controlling/Restricting Agricultural Practice Adverse Collecting Existing Collecting Adverse Spelunking Existing Spelunking Adverse Food Supply Reduction Existing Food Supply Reduction Adverse Groundwater drawdown Existing Groundwater drawdown Adverse Irrigating Existing Irrigating COMMENTS ON MANAGEMENT PRACTICES - The Texas blind salamander is restricted to a small, heavily populated area (approx. 40 sq. miles) around San Marcos, Hays Co., Texas. At the time of listing of the species (1967) the animal was known only from a few localities. Primer's well had not been visited for some years, the well in Wonder Cave was closed, the salamander was only occassionally seen in Ezell's Cave, and salamanders were not seen being washed from the Artesian Well (this is due to no one sampling properly (16)). However, once Ezell's Cave was purchased by The Nature Conservancy, renewed interest led to discoveries of other flourishing populations (12). Much of the habitat is beneath the city of San Marcos and is vulnerable to local changes that could adversely impact the habitat. Urban pollution (e.g., discharge of sewage and industrial wastes and storm sewer runoff) especially in Sink and Purgatory Creeks, and groundwater drawdown of the Edwards Aquifer are two particularly serious future threats (12). Withdrawals for irrigation, industrial and munincipal use have increased such that recharge to the aquifer may not be sufficient in dry years. This could destroy the habitat of the salamander and increase the effects of pollution (12). Longley (11) lists the primary decline of this species in Ezell's Cave (this site only) as over-collecting. Additional causes of decline in Ezell's Cave include the decrease in the population of bats providing feces as nutrient and detritus to the system, loss of input of other organic matter, and the toxic effect of carbide left by spelunkers causing the salamanders to avoid an otherwise preferred area. It is important to note that Longley (11) states that the conditions effecting Ezell's Cave are applicable only to that site and do not reflect the status of the salamander population in general. Longley (11) feels that population size and age structure are indicative of a healthy, expanding population. Management Practices - 1 (DRAFT) - Management Practices Species SALAMANDER, BLIND, TEXAS Species Id ESIS202002 Date 14 MAR 96 UNAPPROVED PLAN: No Recovery Plan has been developed for the Texas Blind Salamander. However, because of the species proximity to the San Marcos ecosystem, reference to the San Marcos Recovery Plan (15) would be appropriate. The Texas blind salamander spends its entire life underground in the pools of the Edwards Aquifer. Drastic declines in numbers of the species at Ezell's Cave, Hays Co., Texas, in the late 1960's lead to its inclusion on the Endangered Species list. Longley (11) attributes this decline to collecting, which has been controlled since the cave was purchased by The Nature Conservancy. He felt that though the species had a restricted range, populations were healthy and not in danger of extinction. Survival of this species is tied to the continued quality of the Edwards Aquifer. This aquifer is receiving increased use as human populations grow on the Edwards Plateau. Continued growth and resulting aquifer use by urban populations as well as agriculture has caused decreased flows of the springs, and as human populations become large, groundwater levels will continue to decline. Eventually some adjacent water bearing strata will contribute greater quantities of water to this area. Some of the adjacent aquifers, especially to the south, contain water of poorer quality (i.e., high in salts or sulfur compounds). Decreasing water quality could impact both the Texas blind salamander and its prey. Monitoring of water levels and quality in the Edwards Aquifer seems advisable, as does regular sampling of the species and its prey. Since the recovery plan for the four Threatened and Endangered San Marcos River species calls for possible augmentation of the Edwards Aquifer recharge, controls on the groundwater pumping of the aquifer, and preparation of water wells to ensure continued flow of the river, impacts on the Texas blind salamander should also be considered before pursuing any of these activities. Longley (11) discovered much about the ecology of the salamander. Efforts should continue to identify individual and population characteristics including: 1) food habits; 2)reproductive parameters; 3) survivorship patterns; and 4) diseases and parasites of the species. The Texas blind salamander should be provided the full protection mandated by Federal and Texas laws. Finally, public awareness of the salamander should be increased through information pamphlets, news releases, and public involvement. These activities could be tied to the San Marcos Ecosystem publicity. Management Practices - 2
                                   (DRAFT) - References
                             Species SALAMANDER, BLIND, TEXAS
                                  Species Id ESIS202002
                                      Date 14 MAR 96



     

References

***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE ***** 01 Stejneger, L. 1896. Description of a new genus and species of blind, tailed batrachian from the subterranean waters of Texas. Proc. Nat. Mus. 18:619-621. 02 Emerson, E.T. 1905. General anatomy of Typhlomolge rathbuni. Proc. Bost. Soc. Nat. Hist. 32:43-76. 03 Eigenmann, C.H. 1909. Cave vertebrates of America: A study in degenerative evolution. Publ. Carnegie Inst. Wash. 104:1-41. 04 Hilton, W.A. 1945. The skeletons of Typhlomolge and Haideotriton. J. Ent. and Zool. 37:100-102. 05 Dundee, H.A. 1957. Partial metamorphosis induced in Typhlomolge rathbuni. Copeia (1):52-53. 06 Mitchell, R.W. and J.R. Redell. 1965. Eurycea tridentifera, a new species of troglobitic salamander from Texas and a reclassification of Typhlomolge rathbuni. Texas J. Sci. 17:12-27. 07 Wake, D.B. 1966. Comparative osteology and evolution of the lungless salamanders, family Plethodontidae. Mem. Southern Calif. Acad. Sci. 4:1-111. 08 Brandon, R.A. 1971. North American troglobitic salamanders: Some aspects of modification in cave habitats with special reference to Gyrinophilus palleucus. Bull. Nat. Speleol. Soc. 33:1-21. 09 Brandon, R.A. 1971. Correlation of seasonal abundance with feeding and reproductive activity in the grotto salamander (Typhlotriton spelaeus). Amer. Mid. Nat. 86:93-100. 10 Brandon, R.A. 1973. Optomotor response and eye structure of the troglobitic salamander Gyrinophilus palleucus. Amer. Midl. Nat. 89:467. 11 Longley, Glenn. 1977. Status of Typhlomolge (=Eurycea) rathbuni, the Texas blind salamander. Rep. on file with the U.S. Fish and Wildl. Serv., Albuquerque, N.M. 12 Russell, William. 1976. Distribution of troglobitic salamanders in the San Marcos area Hays County, Texas. BITE Rep. 7601. Texas Assoc. for Biol. Investigations of Troglobitic Eurycea. Univ. TX, Austin. 13 Potter, Floyd E., Jr. and Samuel Sweet. 1981. Generic boundaries in Texas cave salamanders, and a redescription of Typhlomolge robusta (Amphibia: Plethodontidae). Copeia 1981(1):64-75. 14 Sissom, Stanley L. and James C. Davis. [n.d.] A monographic study of Ezell's Cave Hays County, Texas. Rep. on file with the U.S. Fish and Wildl. Serv., Off. of Endg. Sp., Wash., D.C. 15 U.S. Fish and Wildlife Service. 1985. The San Marcos recovery plan for San Marcos River endangered and threatened species. Prepared by the San Marcos Rcovery Team. U.S. Fish and Wildl. Serv., Albuquerque, NM. 109 pp. 16 Longley, Glenn. 1987. [Letter of June 12, 1987, to Sally Stefferud, U.S. Fish and Wildl. Serv., Albuquerque, NM. ***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY ***** References - 1 (DRAFT) - References Species SALAMANDER, BLIND, TEXAS Species Id ESIS202002 Date 14 MAR 96 01 Longley, G. 1977. Status of Typhlomolge (=Eurycea) rathbuni, the Texas blind salamander. Rep. on file with the U.S. Fish and Wildl. Serv., Albuquerque, New Mexico. 76 pp. 02 Russell, William. 1976. Distribution of troglobitic salamanders in the San Marcos area Hays County, Texas. BITE Rep. 7601. Texas Assoc. for Biol. Investigations of Troglobitic Eurycea. Univ. TX, Austin. References - 2