Phaeognathus hubrichtiRed Hills Salamander

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Geographic Range

The geographic range of Red Hills salamanders (Phaeognathus hubrichti) is restricted to the Red Hills region of south central Alabama, USA. They have been documented in only 6 counties in the state of Alabama (Covington, Crenshaw, Monroe, Butler, Barbour, Conecuh). The Alabama River demarcates the species' western-most boundary and the Conecuh River demarcates their eastern-most boundary. Although they appear to reside in adjacent areas to the north and south, their fossorial tendencies make their geographic range difficult to verify. The total area that is occupied by Red Hills salamanders is estimated to be approximately 25,500 hectares. (Brandon, 1965; Dodd, 1991; Gunzburger and Guyer, 1998; Jordan and Mount, 1975; Parham, et al., 1996; Schwaner and Mount, 1970; Smith, 1978; State of Alabama, 2010)

Habitat

Phaeognathus hubrichti prefers the soft-soiled hills of the Red Hills area and seeks out slopes on mesic ravines that are moist, soft and loamy. It also prefers burrow under full canopy of hardwood trees on relatively high and steep ridges sloping down into slow, shallow streams. Most P. hubrichti burrows are found in the center of such slopes, as this location is the least likely to be affected by erosion. It is often found in abandoned burrows of other ground-dwelling species, as it cannot dig effectively itself. If an abandoned burrow is too small, it adjust the size of the burrow by wiggling into the hole and rolling inside the hole until it is large enough for the salamander’s use. Phaeognathus hubrichti burrows are approximately 40 mm wide with a distinctive oval shape. This species is found at an average elevation of 170 m. (Brandon, 1965; Brandon, 1966; Dodd, 1991; Gunzburger and Guyer, 1998; Jordan and Mount, 1975; Parham, et al., 1996; Schwaner and Mount, 1970; Smith, 1978)

  • Average elevation
    170 m
    557.74 ft

Physical Description

Male Red Hills salamanders range from 180 to 220 mm in length, whereas females range in length from 190 to 230 mm. Males can weigh up to 22 g, but most weigh between 7 and 15 g. Females are considerably lighter, weighing between 6 and 12 g, with a maximum of 14 g. Red Hills salamanders belong to the Plethodontinae family, and therefore are lungless and breath through their moist skin. The skin is dark brown in colour with an occasional light spot interspersed around its body, specifically around the facial region. Some larger males have have pale spots on either side of their body, at the base of their tail. Although Red Hills salamanders are significantly longer than their relatives, they have much smaller limbs. The anterior limbs are approximately 11 mm in length and have 4 toes, and the posterior limbs are approximately 14 mm in length and have 5 toes. They have between 20 and 22 costal grooves along the mid-section, which is significantly more than most salamanders. Red Hills salamanders, like other plethodons, have fixed lower jaws, and barely visible nasolabial grooves on their snouts that assist in chemo-reception. Late term pregnant females have eggs that are clearly visible through her skin along each side of her mid-section. (Bakkegard and Guyer, 2004; Brandon, 1965; Donsky and Boyer, 2010; Highton, 1961; Mcknight, et al., 1991; Means, 2003; Schwaner and Mount, 1970; Smith, 1978)

  • Sexual Dimorphism
  • sexes shaped differently
  • Range mass
    5 to 20 g
    0.18 to 0.70 oz
  • Average mass
    11 g
    0.39 oz
  • Range length
    160 to 250 mm
    6.30 to 9.84 in

Development

Red Hills salamanders sexually mature by 100 mm in length, which is approximately 5 to 6 years of age for females. Males mature by 80 mm in length, which take as little as one year for males. Once eggs hatch, young are similar in appearance to adults, with the exception of their bright red gills, which are laterally positioned between the head and forelimbs. Like their adult counterparts, young also have labial folds, but no eyelids. About 10 days after hatching, young undergo metamorphosis, during which they grow eyelids, lose their labial folds, and reabsorb their gills. Most individuals metamorphose at about 37 mm in length and may have some paleness along the ventral surface after metamorphosis. (Bakkegard and Guyer, 2004; Brandon, 1965; Means, 2003; Smith, 1978; Tilley and Bernardo, 1993)

Reproduction

There is no information available regarding the mating system of Phaeognathus hubrichti. (Bakkegard and Guyer, 2004; Brandon, 1965)

Phaeognathus hubrichti males become reproductively mature in less than a year, whereas females take approximately 6 years to reach reproductive maturity. Phaeognathus hubrichti mates once per year. Once mated, females carry fertilized eggs in their oviducts for approximately 20 days. Eggs are then laid during June or July. After being laid, eggs incubate for another 60 days and then are attached to the walls of the burrow in a space that is moist, but not wet. It typically takes around 20 days for young to hatch and emerge. Females hatch an average of 7 offspring per breeding cycle. Little else is known of the reproductive behavior of this species. (Means, 2003)

  • Breeding interval
    <<Phaeognathus hubrichti>> mates once per year.
  • Breeding season
    Phaeognathus hubrichti lays its eggs in late June-July.
  • Average number of offspring
    7
  • Average time to hatching
    20 days
  • Average age at sexual or reproductive maturity (female)
    6 years
  • Average age at sexual or reproductive maturity (male)
    <1 years

Phaeognathus hubrichti mothers stay close to their eggs during development. If the eggs are disturbed, she may ingest them to prevent losing the energy invested in their development. When carrying fertilized eggs, females aggresively defend themselves by biting. Once the eggs are laid, however, she is relatively less aggressive. Paternal care is thought to be non-existent in this species. There is no further information on parental care in P. hubrichti. (Means, 2003)

Lifespan/Longevity

Red Hills salamanders live for approximately 11 years in the wild, which is determined by counting growth rings on limb bones. They are exceptionally rare and there are no records indicating the average lifespan of captive individuals. However, one female specimen lived for over 6 years in captivity and was able to lay eggs prior to being released. (Bakkegard and Guyer, 2004; Parham, et al., 1996)

  • Average lifespan
    Status: captivity
    6 years
  • Average lifespan
    Status: wild
    11 years

Behavior

Phaeognathus hubrichti is notoriously elusive and was not discovered until 1961. It remains at the entrance of its burrows for up to 12 hours a night, and retreats into its burrow during the day. It hunts only at night and rarely travels extended distances from its burrow in search of prey. When escaping predators, it has an effective body-roll method that allows it to rapidly maneuver through its burrow. (Bakkegard and Guyer, 2004; Bakkegard, 2002; Bakkegard, 2005; Brandon, 1965; Gunzburger and Guyer, 1998; Gunzburger, 1999; Valentine, 1963)

Home Range

There is no information on the average home range size of Red Hills salamanders. They agressively defend their burrow, and use a unique head-butting technique when defending the entrance to the den. When head-butting, individuals thrust themselves from their burrows with their small limbs, driving their head into the intruder. The intruder is startled upon impact and is knocked out of the entrance and down the hill the burrow was created on. This technique is most effective on intruders that are smaller or of comparable size. (Bakkegard and Guyer, 2004; Bakkegard, 2002; Bakkegard, 2005; Dodd, 1990; Dodd, 1991; Gunzburger and Guyer, 1998; Gunzburger, 1999)

Communication and Perception

There is little information available regarding communication and perception in Phaeognathus hubrichti. This species likely does not communicate audibly; however, nasolabial grooves on the snout are thought to assist in chemoreception, and the interior groove is lined with glands. Although individuals are thought to aggressively defend burrows, there is no data to confirm this. Numerous male specimens are documented as having bite marks, suggesting aggressive interactions with conspecifics, possibly as a result of competition for mates or burrows. (Brandon, 1965; Highton, 1961; Means, 2003; Schwaner and Mount, 1970)

Food Habits

Red Hills salamanders are primarily insectivorous, and gut content analyses have revealed a preference for spiders, earthworms, millipedes, beetles, mites and fly larvae. In some instances, they have been seen foraging on snails and molted snake skins. Other foods include fungus and detritus. (Brandon, 1965; Gunzburger, 1999)

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

Predation

Primary predators of Red Hills salamanders are thought to include various species of bird, snakes, and mammals such as coyotes and badgers. When threatened by a potential predator, Red Hills salamanders bare their teeth and may attempt to strike. They are also known to "head-butt" burrow intruders. When head-butting, individuals thrust themselves from their burrows with their small limbs, driving their head into the intruder. The intruder is startled upon impact and is knocked out of the entrance and down the hill the burrow was created on. This technique is most effective on intruders that are smaller or of comparable size. If captured, an individual may gyrate in a circular pattern similar to that of a snake, attempting to loosen the attacker's grip. Its primary form of defense, however, is to remain inside its burrow as much as possible. (Bakkegard and Guyer, 2004; Bakkegard, 2002; Bakkegard, 2005; Brandon, 1965; Gunzburger and Guyer, 1998; Valentine, 1963)

  • Anti-predator Adaptations
  • cryptic

Ecosystem Roles

Phaeognathus hubrichti is an important prey item for a number of different vertebrate species, including various species of snakes, mammals, birds, other amphibians. In addition, this species is insectivorous and my help control a variety of insect pest species. There is no information available regarding potential parasites of this species. (Brandon, 1965; Brandon, 1966; Donsky and Boyer, 2010; Gunzburger, 1999; State of Alabama, 2010)

Economic Importance for Humans: Positive

There are no known positive effects of Phaeognathus hubrichti on humans. (Highton, 1961; Jordan and Mount, 1975; Tilley and Bernardo, 1993; Valentine, 1963)

  • Positive Impacts
  • research and education

Economic Importance for Humans: Negative

There are no known adverse effects of Phaeognathus hubrichti on humans. (Dodd, 1991; Gunzburger and Guyer, 1998)

Conservation Status

Red Hills salamanders are classified as "endangered" on the IUCN's Red List of Threatened Species and has been protected by the United States Endangered Species Act as "threatened" since 1976. This species is found only in south central Alabama and is listed as a protected non-game species by the state of Alabama. Greater than 40% of potential habitat is owned or managed by pulp corporations, and although it does not occur in any officially protected habitat, a little more than 6 hectares have been set aside by private and public ownership to support the conservation and management of this species. Unfortunately, evidence suggests that Red Hills salamanders do not readily re-populate reforested areas, making their recovery significantly more difficult. In 2010, the United States Nature Conservancy purchased 723 hectares of the Red Hills Conservation Area in order to support the long-term protection of this species. The Nature Conservancy, the State of Alabama and the United States Fish and Wildlife Service, continue to work together to protect areas of salamander habitat from potential degradation. (Dodd, 1991; Donsky and Boyer, 2010; Gunzburger and Guyer, 1998; Jordan and Mount, 1975)

Contributors

Chance Reinhart (author), University of Alberta, Augustana Campus, Doris Audet (editor), University of Alberta, Augustana Campus, John Berini (editor), Animal Diversity Web Staff.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

cryptic

having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.

detritus

particles of organic material from dead and decomposing organisms. Detritus is the result of the activity of decomposers (organisms that decompose organic material).

ectothermic

animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature

female parental care

parental care is carried out by females

fertilization

union of egg and spermatozoan

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

fossorial

Referring to a burrowing life-style or behavior, specialized for digging or burrowing.

heterothermic

having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.

insectivore

An animal that eats mainly insects or spiders.

internal fertilization

fertilization takes place within the female's body

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

metamorphosis

A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.

molluscivore

eats mollusks, members of Phylum Mollusca

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

nocturnal

active during the night

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

scavenger

an animal that mainly eats dead animals

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

soil aeration

digs and breaks up soil so air and water can get in

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

threatened

The term is used in the 1994 IUCN Red List of Threatened Animals to refer collectively to species categorized as Endangered (E), Vulnerable (V), Rare (R), Indeterminate (I), or Insufficiently Known (K) and in the 1996 IUCN Red List of Threatened Animals to refer collectively to species categorized as Critically Endangered (CR), Endangered (EN), or Vulnerable (VU).

visual

uses sight to communicate

References

Bakkegard, K. 2002. Activity Patterns of Red Hills Salamanders (Phaeognathus hubrichti) at Their Burrow Entrances. Copeia, Vol. 2002/ No. 3: pp. 851-856. Accessed October 13, 2010 at http://www.bioone.org/doi/abs/10.1643/0045-8511(2002)002%5B0851%3AAPORHS%5D2.0.CO%3B2.

Bakkegard, K. 2005. Antipredator Behaviors of the Red Hills Salamander, Phaeognathus hubrichti. Southeatern Naturalist, Vol. 4/ No.1: pp. 23-32. Accessed October 14, 2010 at http://www.jstor.org/stable/3878155.

Bakkegard, K., C. Guyer. 2004. Sexual Size Dimorphism in the Red Hills Salamander, Phaeognathus hubrichti (Caudata: Plethodontidae: Desmognathinae). Journal of Herpetology, Vol. 38/ No. 1: pp. 8-15. Accessed October 13, 2010 at http://www.jstor.org/stable/1566080.

Brandon, R. 1966. Amphibians and Reptiles Associated with Phaeognathus hubrichti Habitats. Herpetologica, Vol. 22/ No. 4: 308-310. Accessed October 14, 2010 at http://www.jstor.org/stable/3891357.

Brandon, R. 1965. Morphological Variation and Ecology of the Salamander Phaeognathus hubrichti. Copeia, Vol. 1965/No. 1: pp. 67-71. Accessed October 13, 2010 at http://www.jstor.org/stable/1441241.

Dodd, K. 1990. Line Transect Estimation of Red Hills Salamander Burrow Density Using a Fourier Series. Copeia, Vol. 1990/No. 2: pp. 555-557. Accessed October 13, 2010 at http://www.jstor.org/stable/1446359.

Dodd, K. 1991. The status of the Red Hills salamander Phaeognathus hubrichti, Alabama, USA, 1976–1988. Biological Conservation, Vol. 55/ No. 1: pp. 57-75. Accessed October 13, 2010 at http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V5X-48XKJ8P-5H&_user=1067472&_coverDate=12%2F31%2F1991&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1498512298&_rerunOrigin=scholar.google&_acct=C000051251&_version=1&_urlVersion=0&_userid=1067472&md5=29bd1bac697f13a71e3daee9e4cd2841&searchtype=a.

Donsky, A., R. Boyer. 2010. "Nature Conservancy Land Purchase Could Save Alabama's Red Hills Salamander" (On-line). Accessed November 11, 2010 at http://www.treehugger.com/files/2010/04/nature-conservancy-land-purchase-could-save-alabama-red-hills-salamander.php?campaign=th_rss&utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+treehuggersite+%28Treehugger%29.

Gunzburger, M. 1999. Diet of the Red Hills Salamander Phaeognathus hubrichti. Copeia, Vol. 1999/ No. 2: pp. 523-525. Accessed October 13, 2010 at http://www.jstor.org/stable/1447504.

Gunzburger, M., C. Guyer. 1998. Longevity and Abandonment of Burrows Used by the Red Hills Salamander (Phaeognathus hubrichti). Journal of Herpetology, Vol. 32/ No. 4: pp. 620-623. Accessed October 13, 2010 at http://www.jstor.org/stable/1565226.

Highton, R. 1961. A New Genus of Lungless Salamander from the Coastal Plain of Alabama. Copeia, Vol. 1961/ No.1: pp. 65-68. Accessed October 13, 2010 at http://www.jstor.org/stable/1440175.

Jordan, R., R. Mount. 1975. The Status of the Red Hills Salamander, Phaeognathus hubrichti Highton. Journal of Herpetology, Vol. 9/ No. 2: pp. 211-215. Accessed October 13, 2010 at http://www.jstor.org/stable/1563039.

Mcknight, M., K. Dodd, C. Sposlky. 1991. Protein and Mitochondrial DNA Variation in the Salamander Phaeognathus hubrichti. Herpetologica, Vol. 47/ No. 4: pp. 440-447. Accessed October 13, 2010 at http://www.jstor.org/stable/3892849.

Means, B. 2003. "Notes on the Reproductive Biology of the Alabama Red Hills Salamander (Phaeognathus hubrichti )" (On-line). Contemporary Biology. Accessed October 13, 2010 at http://www.contemporaryherpetology.org/ch/2003/3/.

Parham, J., K. Dodd, G. Zug. 1996. Skeletochronological Age Estimates for the Red Hills Salamander, Phaeognathus hubrichti. Journal of Herpetology, Vol. 30/ No. 3: pp. 401-404. Accessed October 13, 2010 at http://www.jstor.org/stable/1565178.

Schwaner, T., R. Mount. 1970. Notes on the Distribution, Habits, and Ecology of the Salamander Phaeognathus hubrichti Highton. Copeia, Vol. 1970/ No. 3: pp. 571-573. Accessed October 13, 2010 at http://www.jstor.org/stable/1442289.

Smith, H. 1978. A Guide to Field Identification: Amphibians of North America. Racine, Wisconsin: Western Publishing Company.

State of Alabama, 2010. "Official Amphibian: Red Hills Salamander" (On-line). Official Symbols and Emblems of Alabama. Accessed November 11, 2010 at http://www.archives.state.al.us/emblems/st_amphib.html.

Tilley, S., J. Bernardo. 1993. Life History Evolution in Plethodontid Salamanders. Herpetologica, Vol. 49/ No. 2: pp. 154-163. Accessed October 13, 2010 at http://www.jstor.org/stable/3892792.

Valentine, B. 1963. The Plethodontid Salamander Phaeognathus: Collecting Techniques and Habits. Journal of Ohio Herpetological Society, Vol.4/ No. 1\2: pp. 49-54. Accessed October 13, 2010 at http://www.jstor.org/stable/1562580.