Desmognathus quadramaculatus

Geographic Range

Black-bellied salamanders ( Desmognathus quadramaculatus ) are found in mountainous regions in southern West Virginia and soputhwestern Virginia, with a range continuing southward to eastern Tennessee (south of the Tennessee Valley divide) and western North Carolina to northern Georgia. This includes the far western portion of South Carolina. They have been introduced into additional locations in Georgia and South Carolina due to their use as fish bait.

• Biogeographic Regions
• nearctic nearctic
  • introduced introduced
  • native native

Habitat

Black-bellied salamander habitat consists of rivers and streams with waterfalls and swift currents (although no current speed has been published). They burrow under rocks into the soil if the current is too harsh, or if hiding from larger predators.They also use rocks on the edge of rivers and rocks exposed to the sun for basking.

Juveniles tend to stay in fast-moving riffles of the streams. Adults burrow between pebbles and soil to ambush their prey. The elevational range at which these salamanders are found is between 460 to 1676 meters. These salamanders are commonly found in cooler freshwater temperatures, 10- 17.7 degrees C. The depths at which they forage are not known, although all ages are known to inhabit the stream beds.

• Habitat Regions
• freshwater freshwater

• Aquatic Biomes
• rivers and streams

Physical Description

Black-bellied salamanders are thick-bodied, with a short curled tail. They are the largest species in the genus Desmognathus . Their tail is strongly keeled and they have 14 costal grooves. These salamanders can be mostly black, gray, or brown with a black belly and lateral white spots going down the body. They have short, sharp, black toes. Occasionally, some will have a vertical red stripe along the tail. In some parts of Tennessee, some black-bellied salamanders can have a brownish tint with black along the body. The older males tend to be blacker with larger features like premaxillary teeth and a more defined cloacal lips. Both adults males' and females' SVL (snout-vent lengths) are typically 75-80 mm (maximum 120 mm SVL) and total lengths can range between 90-210 mm. Males typically are larger than females, by a factor of 15%.

The hatchlings' color is typically brown and they possess up to eight white spots between their limbs. The length ranges from 11 to 16 mm. As age increases, white external gills will become darker. Young juveniles have bellies that are white in pigmentation, and within months they will change to black.

• Other Physical Features
• ectothermic ectothermic
• heterothermic heterothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• male larger
• sexes colored or patterned differently

Development

Black-bellied salamanders' first stage of life is a fertilized egg that hatches in a 1 to 4 month period between May and September. These salamanders remain in their larval stage for 12 (lower elevations in Tennessee) to 60 (higher elevations in West Virginia) months after which they undergo metamorphosis. At this stage they are about 34 to 54 mm in length. The range for time to metamorphosis is likely linked to growth rate and climate conditions; individuals at higher elevations were larger and remained in the larval stage for a longer time period. Like all species of salamanders, they likely exhibit indeterminate growth.

• Development - Life Cycle
• metamorphosis metamorphosis
• indeterminate growth indeterminate growth

Reproduction

Black-bellied salamanders are polygynous in that one male mates with multiple females. The males use a tactic of rubbing against the female and waiving their arm to attract and stimulate the female. The spermatophores are clusters of sperm deposited by the male. Sometimes males drop their spermatophores without females' attention. A spermatophore is a ball-like capsule of sperm. Once the female picks up the spermatophores in the cloaca a reproductive pocket they will lay eggs within days.

• Mating System
• polygynous polygynous

Black-bellied salamanders reproduce with males courting the females. Males are mature around ages 3.5 to 6 and females are mature at ages 4.5 to 7. Male tactics of courting include arm waving and rubbing against the female body to stimulate the female. Males drop their sperm in a cluster called spermatophores in the substrate of the flowing water. Males don't have to use a mating attraction to drop their spermatophores until females pick them up. Any female can pick them up and store them in their cloacas.

Females will lay eggs every other year towards the end of the spring to early summer in fast-flowing water like waterfalls, under rocks, or on the river's edge. Each egg, averaging a diameter of 3.9 mm, is suspended 3 mm by an elastic pedical support it in fast flowing water. Egg clusters range from 21 to 65 eggs and they look like non-pigmented flattened grapes. Their dry weight has been reported as 188 to 203 mg, but birth mass has not been reported. Females guard their eggs until the late summer when hatching begins (1 to 4 months post-laying, average is 2 months). Is not known if females help the young after the hatching period. The larvae lengths can be 35 to 54 mm in 8 to 48 months. The first two months post-hatching, the larva live off of their yolk masses. It takes 3 to 4 years before the larvae metamorphose into adults.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• fertilization fertilization
  • internal internal
• oviparous oviparous

Once black-bellied salamanders lay their eggs, females guard the eggs until hatching. Males leave the eggs while females stay until they hatch. The hatchlings live off their yolk masses post-hatching for 1 to 2 months until they learn to forage on their own.

• Parental Investment
• female parental care female parental care
• pre-fertilization
  • protecting
• pre-hatching/birth
  • protecting
    • female

Lifespan/Longevity

Black-bellied salamander longest known lifespan in the wild is 15 years. There is no information on in captivity lifespan because these salamanders are not kept in captivity.

Behavior

Black-bellied salamanders are most active during warmer months, but can be active year-round if temperatures are mild. Black-bellied salamanders are nocturnal as juveniles, but can be diurnal as adults. They are thought to be one of the most aquatic of all members of the genus Desmognathus . They forage in their creeks or on the riverbanks. They are very territorial over their refugia, and have been known to fight with members of their own species, as well as predators. These refugia are located in the dirt or in between rocks, and they often use a single refugia or rotate around one primary and few secondary refugia. In the water, they frequently dig and sit-and-wait in their refugia to attack prey.

• Key Behaviors
• fossorial fossorial
• natatorial natatorial
• diurnal diurnal
• nocturnal nocturnal
• motile motile
• sedentary sedentary
• territorial territorial
• social social

Home Range

Individuals use a minimum home area of 1,207 square centimeters. This is centered around one or few refugia. It is common for individual black-bellied salamanders to have home ranges that overlap. They do defend their refugia, but territory size has not been published.

Communication and Perception

Black-bellied salamanders use deterring chemical cues against predators. They release them on the substrate in which they walk on land or aquatic and potential predators avoid these areas. There are many of glands like the cloacal and mucous glands from which they secrete chemical cues.

The chemical cues from the cloacal gland can also be secreted in feces.

Black-bellied salamanders will be aggressive towards other individuals of their species that approach their refugia. Thus, it is assumed that visual and tactile cues are involved.

• Communication Channels
• visual visual
• tactile tactile
• chemical chemical

• Other Communication Modes
• scent marks scent marks

• Perception Channels
• visual visual
• chemical chemical

Food Habits

The diet of black-bellied salamanders includes aquatic worms, crayfish, and mostly aquatic larva. Small adult insects include flies ( Diptera ), caddisflies ( Trichoptera ), stoneflies ( Plecoptera ), and mayflies ( Ephemeroptera ). They can also eat butterflies, bees, moths, centipedes, and spiders. Older adults can even eat smaller salamanders, like those in the genus Plethodon or Eurycea . Although they can be cannibalistic, diet studies have shown that other salamanders make up miniscule part of their diets.

With age, their eating habits progress from aquatic prey to aerial prey. As adults they are very aggressive hunters towards other salamanders and insects, ambushing prey from rocks. They will sometimes go on land up to 9.1 km to forage in leaf patches. The most abundant time to forage for post metamorphic of the months October through April. (Lannoo, 2005). About 97% of adult black-bellied salamanders forage above the waters edge and in summer months due to warmer temperature they move into deeper waters.

• Primary Diet
• carnivore carnivore
  • eats eggs
  • insectivore insectivore
  • eats non-insect arthropods
  • vermivore

• Animal Foods
• amphibians
• eggs
• insects
• terrestrial non-insect arthropods
• terrestrial worms

Predation

Black-bellied salamanders have a few known predators. Predators include northern short-tailed shrews ( Blarina brevicauda ) and garter snakes ( Thamnophis ), water snakes ( Nerodia ), crayfish, spring salamanders ( Gyrinophilus porphyriticus ), and aquatic invertebrates.

Black-bellied salamanders have a defensive strategy against shrews by showing off the white lining in the jaws and snapping towards them. They will bite the head or the body of the predator. If garter snakes latch onto the salamander, they twist their body around, attempting to free themselves while biting the snake. The snake may loosen its grip and the salamanders can escape. These salamanders can also drop their tails in the event of attempted predation.

The other predators mainly prey on the larva and juveniles. Studies show that the salamanders will flee from predators depending on the season, predator size, and predator species.

Ecosystem Roles

Black-bellied salamanders are host of numerous parasites from multiple taxa. Species of protozoans include Cryptobia borreli , Cytamoeba bacterifera , Eutrichomastix batrachorum , Hexamastix batrachorum , Hexamitus batrachorum , Hexamitus intestinalis , Karotomorpha swezi , Prowazekella longifilis , and Tritrichomonas augusta . Species of flukes (trematodes) include Brachycoelium hospitale and Diplostomulum desmognathi . There have been some unidentified fluke metacercariae, as well. The species of tapeworms (cestodes) are Crepidobothrium cryptobranchi and cysts from the Family Proteocephalidae. Species of roundworms (nematodes) include Capillaria inequalis , Omeia papillocauda , Oxyuris magnavulvaris , and cysts from the Family Acuariidae. One parasitic acanthocephalan is Centrorynchus conspectus .

Leeches are the most common ectoparasite found, but no species have been reported.

Economic Importance for Humans: Positive

Black- bellied salamanders are occasionally used as fishing bait. No other positive economic impacts have been reported.

Economic Importance for Humans: Negative

There are no negative economic impacts of black-bellied salamanders.

Conservation Status

Black-bellied salamanders are listed as a species of "Least Concern" on the IUCN Red List. Populations across the geographic range are stable but some populations could be threatened locally by their use as fishing bait. Their populations can also decline from pollution of streams near mining areas as acidification is often a concern. Jensen (2008) reports the use of commercial bleach to drive salamanders from their refugia. Black-bellied salamanders have no special status on the US Federal list, CITES, and State of Michigan lists. Due to their limited range, they are listed as a Species of Concern in West Virginia. As a relatively common species elsewhere in their range, no conservation efforts are in place.

Additional Links

AmphibiaWeb

Encyclopedia of Life

Contributors

Elisha Nicholas (author), Radford University, Alex Atwood (editor), Radford University, Karen Powers (editor), Radford University, Joshua Turner (editor), Radford University, Tanya Dewey (editor), University of Michigan-Ann Arbor.

References

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Austin Jr., R., C. Camp. 1992. Larval development of black-bellied salamanders, Desmognathus quadramaculatus, in northeastern Georgia. Herpetologica , 48/3: 313-317.

Cecala, K., S. Price, M. Dorcas. 2007. Diet of larval red salamanders (Pseudotriton ruber). Journal of Herpetology , 41/4: 741-745.

Hileman, K., E. Brodie Jr.. 1994. Survival strategies of the salamander Desmognathus ochrophaeus: Interaction of predator-avoidance and anti-predator mechanisms. Animal Behavior , 47/1: 1-6.

IUCN SSC Amphibian Specialist Group, 2014. "Desmognathus quadramaculatus" (On-line). The IUCN Red List of Threatened Species 2014:e.T59256A64000134. Accessed September 18, 2017 at http://dx.doi.org/10.2305/IUCN.UK.2014-3.RLTS.T59256A64000134.en .

Jacobs, A., D. Taylor. 1992. Chemical communication between Desmognathus quadramaculatus and Desmognathus monticola. Journal of Herpetology , 26/10: 93-95.

Jensen, J. 2008. Amphibians and Reptiles of Georgia . Athens, GA: University of Georgia Press.

Lannoo, M. 2005. Amphibian Declines: The Conservation Status of United States Species . Oakland, CA: Regents of the University of California.

Lawhorn, M., L. Garrett, S. Graham, L. Giovanetto, B. Edelbrock. 2017. Desmognathus quadramaculatus (black-bellied salamander). Herpetological Review , 48/1: 153-154.

Martof, B., W. Palmer, J. Bailey, J. Harrison III. 1980. Amphibians and Reptiles of the Carolinas and Virginia . Chapel Hill, NC: The University of North Carolina Press.

Mitchell, J., W. Gibbons. 2010. Salamanders of the Southeast . Athens, GA: University of Georgia Press.

Mitchell, J., K. Reay. 1999. Atlas of Amphibians and Reptiles in Virginia . Richmond, VA: Virginia Department of Game and Inland Fisheries.

Petranka, J. 2010. Salamanders of the United States and Canada . Washington, D.C.: Smithsonian Institute.

Roudebush, R., D. Taylor. 1987. Chemical communication between two species of desmognathine salamanders. Copeia , 3: 744-748.

Wilson, L. 1995. The Land Manager's Guide to the Amphibians and Reptiles of the Soth . Chapel Hill, NC: The Nature Conservancy.