Salamandrina perspicillata

Geographic Range

The northern spectacled salamander (Salamandrina perspicillata) is native to the Palearctic region. The species can be found in northern Italy, predominantly in the Appenine Mountains. The southern boundary of the northern spectacled salamander is the province of Caserta, which is in the Campania region of Italy, and the northern boundary is the province of Pavia, which is in the Lombardy region in Italy. The species can be found as far west as the west coast of Italy and as far east as the Marche Region of Italy. Additional sources claim the species can also be found further east in the Apulia Region of Italy. (Liuzzi, et al., 2011; Romano, et al., 2009)

Habitat

The northern spectacled salamander is primarily terrestrial and lives in heavily forested habitats in mountainous areas. These forests are damp and shaded, and they contain large limestone rock formations that provide shelter for the salamander. It can be found in areas with an elevation as low as 50 meters and as high as 1500 meters, but it is typically located between 200 meters and 900 meters. The female spectacled salamander will travel to freshwater habitats, such as ponds, streams, and various temporary pools of water, to lay eggs. (Angelini, et al., 2008; Costa, et al., 2014; Romano and Ficetola, 2010; Romano, et al., 2009)

  • Aquatic Biomes
  • lakes and ponds
  • rivers and streams
  • temporary pools
  • Range elevation
    50 to 1500 m
    164.04 to 4921.26 ft

Physical Description

The northern spectacled salamander is ectothermic and bilaterally symmetrical. Bovero et al. (2006) found the average length of the adult northern spectacled salamander is 106.1 mm and the average snout-vent length is 42.8 mm. The total observed length of the adult northern spectacled salamander ranges from 92 mm to 133 mm and the snout vent length ranges from 36 mm to 50 mm. The female spectacled salamander is usually larger than the male, but no sources have been found to confirm this with exact measurements.

Angelini et al. (2008) found the average total length of the pre-metamorphic spectacled salamander ranges from 17.7 mm to 23.4 mm. The pre-metamorphic salamander does not have ventral pattern coloration.

The adult northern spectacled salamander has a yellow v-shaped spot on its head that resembles spectacles, which gives the salamander its name. The salamander has areas of red, white, and black spots on its ventral side. The extremities and tail are red, and the trunk and body are black and white speckled. The color distribution of the northern spectacled salamander is unique to each salamander, which allows for differentiation among other individuals of the same species. Northern spectacled salamanders of the same population typically resemble each other more closely than spectacled salamanders from different populations. (Angelini, et al., 2008; Bovero, et al., 2006; Costa, et al., 2009; Sebastiano, et al., 2012)

  • Sexual Dimorphism
  • female larger
  • Range length
    92 to 133 mm
    3.62 to 5.24 in
  • Average length
    106.1 mm
    4.18 in

Development

The salamander begins as an egg with a yolk of 1.5 mm to 3.7 mm. The egg hatches within 12 to 37 days as a larva, and the larva is usually 7 mm to 13 mm in length. Metamorphosis occurs when the salamander reaches 20 mm to 35 mm in length, which is usually two to five months after it hatches. The larva does not have any ventral color patterns before metamorphosis, but it develops the ventral color patterns of an adult within a few months after metamorphosis. Similar to tree ring counting, the age of larvae and adults can be determined under a microscope experimentally by counting lines of arrested growth (LAG) in the phalanx, a bone in the toe. One LAG represents one year of growth in the salamander, and sexual maturity is reached in the salamander when the distance between the LAGs narrows drastically.

Sex is difficult to determine in the northern spectacled salamander based on physical characteristics. The male salamander has a more noticeable opening for the cloaca, but this is not considered a reliable determination of sex. One behavior that is often used to determine this salamander's sex is if the salamander is seen in water. The male avoids water, whereas the female salamander goes to water to lay its eggs. (Bovero, et al., 2006; Bruni and Romano, 2011; Lannoo, 2005)

Reproduction

The northern spectacled salamander is polygynandrous. Rovelli et al. (2015) found two to four males fertilize the female, on average. The male who is most genetically unlike the female typically fathers the most offspring, which indicates that the female spectacled salamander may be able to detect the amount of genetic variance.

The salamander breeds each year from April to May. The male often begins the mating process by standing on its hind legs and excreting a mucus trail. It is inferred that this mucus trail may release chemical cues to attract females, but this has not been experimentally supported. When a female approaches, the male runs in front of her until she stops moving. If the female does not stop moving, the male stops the pre-mating rituals and waits for another female. If the female stops moving, the male quickly moves his tail back and forth, and the mating salamanders begin to circle each other. Then, the male drops a spermatophore, a sperm packet, in front of the female. The female picks up the spermatophore, and it is moved internally into her cloaca.

While mating, the male can become very aggressive if another male tries to interrupt the process. The mating male will stop the mating process if it sees another male, and it will attempt to scare the other male away by biting it. After the intruding male leaves, the mating male will return to the female and attempt to continue the mating process. (Bruni and Romano, 2011; Rovelli, et al., 2015)

The northern spectacled salamander is iteroparous and reproduces sexually. The female salamander reaches sexual maturity around four to five years old, but the male age of sexual maturity is unknown. The salamander breeds once yearly from April to May. The salamander has external sperm deposition, but fertilization is internal. The female can store this sperm for up to six months, which is the longest known sperm storage period among all salamanders.

The female salamander is oviparous and lays 20 to 50 eggs. These eggs take 12 to 37 days to hatch in water that is 14 degrees Celsius, but they can take up to 50 days to hatch in cooler water. The larva is independent as soon as it hatches. (Boscherini and Romano, 2011; Bovero, et al., 2006; Bruni and Romano, 2011; Romano, et al., 2008; Sparreboom, 2014)

  • Breeding interval
    Northern spectacled salamanders breed once yearly
  • Breeding season
    April to May
  • Range number of offspring
    20 to 50
  • Range time to hatching
    12 to 50 days
  • Average time to independence
    0 days
  • Range age at sexual or reproductive maturity (female)
    4 to 5 years

There is very little parental involvement in the offspring of the northern spectacled salamander. The female protects the eggs for a short time while she is spawning them, which can take about 13 days. While spawning, if a predator approaches the eggs, she begins defending the eggs by creating water currents with her body movements. The female continues making the currents until the predator gets swept away. If the predator does not get swept away by the current, the salamander pushes the small predator away with her head. After the female finishes ovipositing, she leaves the area and no longer protects the eggs. The male exhibits no parental care beyond the mating process. (Boscherini and Romano, 2011)

  • Parental Investment
  • pre-hatching/birth
    • protecting
      • female

Lifespan/Longevity

The expected lifespan of the northern spectacled salamander after reaching sexual maturity is about six to seven years. Because sexual maturity is reached between four and five years old, the total expected lifespan in the wild is 12 years. In captivity, the salamander can live between 10 and 12 years. Annual mortality rates are 10-15%, and the main cause of death is lack of food. (Angelini, et al., 2010; Bovero, et al., 2006; Lannoo, 2005)

  • Typical lifespan
    Status: wild
    12 (high) years
  • Typical lifespan
    Status: captivity
    10 to 12 years

Behavior

The northern spectacled salamander is a motile, terricolous species. The salamander has been located at depths of 20-135 cm under the soil surface during summer and winter. The species has also been seen between 130-170 cm above the surface in rock formations during spring and summer. It is suggested that the spectacled salamander primarily uses both of these locations for shelter and protection against predators.

The species is nocturnal and crepuscular, and it is most active from 1800-0000h. The salamander is most active in dim light and mostly dark conditions. It also tends to be more active during rainy days because the cloud cover provides more dim conditions.

The salamander is mostly solitary, but it is not territorial. The salamander often shares the same spawning location with other individuals of the species. The communication among individuals of the species is mostly unknown. The only known social interactions that have been observed between salamanders occur during the reproduction process. During reproduction, the individual uses tail movements to communicate with its potential mate. The salamander does not make physical contact with its mate, which is uncommon for salamanders. (Bruni and Romano, 2011; Lannoo, 2005; Vignoli, et al., 2014)

Home Range

The territory size of the northern spectacled salamander (and other members of its genus) is unknown.

Communication and Perception

The northern spectacled salamander uses sight, touch, and vibrations to perceive its environment, but it primarily uses chemical cues. The salamander can detect its own scent trail, which allows the salamander to find its breeding site and stay within its home range. The female salamander uses its scent trail to find its oviposition site.

Tail movement is a major mode of communication between potential mates. The way the female salamander moves its tail communicates to the male whether she will mate with him. It is unknown if this tail movement is used as a visual cue or if the tail movement is used to distribute chemical cues through the air. The male salamander aggressively moves its tail if it sees another male who may interrupt the mating. If the other male does not respond to the tail movement, the mating male may bite the other male until it leaves. Social communication in the northern spectacled salamander outside of the reproduction process is mostly unknown. (Bruni and Romano, 2011; Vignoli, et al., 2012)

Food Habits

The northern spectacled salamander is primarily an insectivore, but spiders, mollusks, and worms can also make up a part of its diet. The main food source of the northern spectacled salamander is springtails (Collembola), spiders (Aranea), and beetle larvae (Coleoptera).

The northern spectacled salamander is the only known salamander with a specialized diet. The salamander is typically highly specialized on springtails in spring, and it can be specialized on springtails, spiders, and beetle larvae in autumn. The more specialized salamander is able to find and catch prey more effectively than the generalist of the same species. Costa et al. (2015) found that the species is made up mostly of specialists, which is uncommon among other species. (Costa, et al., 2014; Costa, et al., 2015; Sebastiano, et al., 2012)

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

Predation

Piazzini et al. (2011) found that the introduced brown trout (Salmo trutta) and the Italian white-clawed crayfish (Austropotamobius fulcisianus) are predators to the northern spectacled salamander. The main anti-predator adaptation used by the adult salamander is that it can look dead to predators when it feels threatened, which is known as thanatosis.

A leech (Trocheta bykowskii), and two types of caddisfly larvae (Potamophylax cingulatus and Halesus appenninus) are the main predators of the eggs of the northern spectacled salamander. The eggs and larvae of the northern spectacled salamander have no known anti-predator adaptations, but the mother often guards her eggs while laying them to limit predation. (Boscherini and Romano, 2011; Lannoo, 2005; Piazzini, et al., 2011; Romano, et al., 2008)

Ecosystem Roles

The northern spectacled salamander preys on springtails (Collembola), which are invertebrate decomposers. Potentially, the salamander plays a role in controlling the populations of these invertebrates in forest environments. Consuming and controlling these populations also aids in nutrient recycling. The salamander, and its eggs, also acts as a food source for the brown trout (Salmo trutta), Italian white-clawed crayfish (Austropotamobius fulcisianus), a leech (Trocheta bykowskii), and two types of caddisfly larvae (Halesus appenninus and Potamophylax cingulatus).

Contemporary sources cite that P. Sonsino (1896) found "entozoi", which are generally parasitic worms not confined to a single phylum, are parasitic to the northern spectacled salamander. It is difficult to determine the reliability of this source because it is over 100 years old and in a different language. (Costa, et al., 2014; Yildirimhan, et al., 2005)

Economic Importance for Humans: Positive

The northern spectacled salamander is of little known positive economic importance for humans.

Economic Importance for Humans: Negative

There are no known adverse effects of the northern spectacled salamander on humans.

Conservation Status

The northern spectacled salamander is considered a species of "Least Concern" on the IUCN Red List, and there is no special status listed for the species on the US Federal List or the CITES appendices. Water pollution and loss of habitat have affected some populations of the species but have not caused a drastic decline in the species. An introduced predator, the brown trout (Salmo trutta), is a potential threat to some populations of the salamander. Although this species is not considered threatened, some ares of Italy have implemented laws to protect the salamander. (Lannoo, 2005; Romano, et al., 2009)

Contributors

Mariah Mays (author), Radford University, Cari Mcgregor (editor), Radford University, Zeb Pike (editor), Radford University, Karen Powers (editor), Radford University, April Tingle (editor), Radford University, Jacob Vaught (editor), Radford University, Tanya Dewey (editor), University of Michigan-Ann Arbor.

Glossary

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

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

crepuscular

active at dawn and dusk

ectothermic

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

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.

freshwater

mainly lives in water that is not salty.

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.

motile

having the capacity to move from one place to another.

mountains

This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.

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.

polygynandrous

the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

scent marks

communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them

seasonal breeding

breeding is confined to a particular season

sexual

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

solitary

lives alone

sperm-storing

mature spermatozoa are stored by females following copulation. Male sperm storage also occurs, as sperm are retained in the male epididymes (in mammals) for a period that can, in some cases, extend over several weeks or more, but here we use the term to refer only to sperm storage by females.

tactile

uses touch to communicate

terrestrial

Living on the ground.

vibrations

movements of a hard surface that are produced by animals as signals to others

visual

uses sight to communicate

References

Angelini, C., D. Antonelli, C. Utzeri. 2008. A multi-year and multi-site population study on the life history of Salamandrina perspicillata (Savi, 1821) (Amphibia, Urodela). Amphibia-Reptilia, 29/2008: 161-170.

Angelini, C., D. Antonelli, C. Utzeri. 2010. Capture-mark-recapture analysis reveals survival correlates in Salamandrina perspicillata (Savi, 1821). Amphibia-Reptilia, 31/1: 21-26.

Boscherini, A., A. Romano. 2011. Parental care in Salamandrina perspicillata (Amphibia, Salamandridae): Egg defence against caddisfly larvae. North-Western Journal of Zoology, 7/1: 167-170.

Bovero, S., C. Angelini, C. Utzeri. 2006. Aging Salamandrina perspicillata (Savi, 1821) by skeletochronology. Acta Herpetologica, 1/2: 153-158.

Bruni, G., A. Romano. 2011. Courtship behaviour, mating season and male sexual interference in Salamandrina perspicillata (Savi, 1821). Amphibia-Reptilia, 32/1: 63-76.

Costa, A., S. Salvidio, M. Posillico, T. Altea, G. Matteucci, A. Romano. 2014. What goes in does not come out: Different non-lethal dietary methods give contradictory interpretation of prey selectivity in amphibians. Amphibia-Reptilia, 35/2: 255-262.

Costa, A., S. Salvidio, M. Posillico, G. Matteucci, B. De Cinti, A. Romano. 2015. Generalisation within specialization: Inter-individual diet variation in the only specialized salamander in the world. Scientific Reports, 5/2015: 13260.

Costa, C., C. Angelini, M. Scardi, P. Menesatti, C. Utzeri. 2009. Using image analysis on the ventral colour pattern in Salamandrina perspicillata (Amphibia: Salamandridae) to discriminate among populations. Biological Journal of the Linnean Society, 96/1: 35-43.

Lannoo, M. 2005. Amphibian Declines: The Conservation Status of United States Species. Berkeley, California: University of California Press.

Liuzzi, C., F. Mastropasqua, D. Salvi. 2011. New distribution and genetic data extend the ranges of the spectacled salamanders, genus Salamandrina, in the Apulia region (south Italy). Acta Herpetologica, 6/2: 315-321.

Piazzini, S., T. Caruso, L. Favilli, G. Manganelli. 2011. Role of predators, habitat attributes, and spatial autocorrelation on the distribution of eggs in the northern spectacled salamander (Salamandrina perspicillata). Journal of Herpetology, 45/3: 389-394.

Romano, A., S. Cristiano, M. Francesca, F. David, R. Bernardino. 2008. Egg predators of an endemic Italian salamander, Salamandrina perspicillata (Savi, 1821). Acta Herpetologica, 3/1: 71-75.

Romano, A., G. Ficetola. 2010. Ecogeographic variation of body size in the spectacled salamanders (Salamandrina): Influence of genetic structure and local factors. Journal of Biogeography, 37/12: 2358-2370.

Romano, A., M. Mattoccia, V. Sbordoni, F. Andreone, C. Corti. 2009. "Salamandrina perspicillata" (On-line). The IUCN Red List of Threatened Species 2009: e.T136135A4248006. Accessed January 28, 2016 at http://dx.doi.org/10.2305/IUCN.UK.2009.RLTS.T136135A4248006.en.

Rovelli, V., E. Randi, F. Davoli, D. Macale, M. Bologna, L. Vignoli. 2015. She gets many and she chooses the best: Polygynandry in Salamandrina perspicillata (Amphibia: Salamandridae). Biological Journal of the Linnean Society, 116/3: 671-683.

Sebastiano, S., R. Antonio, O. Fabrizio, O. Dario, M. Roberta. 2012. Different season, different strategies: Feeding ecology of two syntopic forest-dwelling salamanders. Acta Oecologica, 43/2012: 42-50.

Sparreboom, M. 2014. Salamanders of the Old World. Zeist, The Netherlands: KNNV Publishing.

Ventura, A., C. Ciofi, C. Natali, M. Mattoccia. 2015. Development of microsatellites for the genus Salamandrina: A tool to discriminate between northern and southern spectacled salamanders (Salamandrina perspicillata and Salamandrina terdigitata) and their hybrids. Biochemical Systematics and Ecology, 63/2015: 170-173.

Vignoli, L., R. Silici, A. Bissattini, M. Bologna. 2012. Aspects of olfactory mediated orientation and communication in Salamandrina perspicillata (Amphibia Caudata): An experimental approach. Ethology Ecology & Evolution, 24/2: 165-173.

Vignoli, L., M. D'Amen, F. Della Rocca, M. Bologna, L. Luiselli. 2014. Contrasted influences of moon phases on the reproduction and movement pattems of four amphibian species inhabiting different habitats in central Italy. Amphibia-Reptilia, 35/2: 247-254.

Yildirimhan, H., C. Bursey, S. Goldberg. 2005. Helminth parasites of the Caucasian salamander, Mertensiella caucasica, from Turkey. Comparative Parasitology, 72/1: 75-87.