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This article is about the animal. For other uses, see Newt (disambiguation).
"Eft" redirects here. For other uses, see EFT.
Temporal range: Late Cretaceous–Recent[1]
Neurergus Kaiseri.jpg
Kaiser's spotted newt
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Amphibia
Order: Urodela
Family: Salamandridae
Subfamily: Pleurodelinae

14–17 extant and six fossil genera, see text

A newt is a semiaquatic[2] amphibian of the family Salamandridae, although not all aquatic salamanders are considered newts. Newts are classified as a part of the salamandrid subfamily Pleurodelinae, and can be found in North America, Europe and Asia.

Newts metamorphose through three distinct developmental life stages: aquatic larva, terrestrial juvenile (called an eft[3]), and adult. Adult newts have lizard-like bodies and may be either fully aquatic, living permanently in the water, or semiaquatic, living terrestrially, but returning to the water every year to breed.

Newts are found across Europe, North America, Asia and Japan but a number of populations are threatened due to pollution or destruction of their breeding sites and terrestrial habitats.


The Old English name of the animal was efte, efeta (of unknown origin), resulting in Middle English eft; this word was transformed irregularly into euft, evete, or ewt(e). The initial 'n' was added from the indefinite article 'an' by provection (juncture loss) ("an eft" -> "a n'eft" -> ...) by the early 15th century.[4]The form 'newt' appears to have arisen as a dialectal variant of eft in Staffordshire, but entered Standard English by the Early Modern period (used by Shakespeare in Macbeth iv.1).[5] The regular form eft, now only used for newly metamorphosed specimens, survived alongside newt, especially in composition, the larva being called "water-eft" and the mature form "land-eft" well into the 18th century, but use of the simplex "eft" as equivalent to "water-eft" has been in use since at least the 17th century.[6]

Dialectal English and Scots also has the word ask (also awsk, esk in Scots[7]) used for both newts and wall lizards, from Old English āþexe, from Proto-Germanic *agiþahsijǭ, literally "lizard-badger" or "distaff-like lizard" (compare German Eidechse and Echse, both "lizard"; *agi- is ultimately cognate with Greek ὄφις "snake", from Proto-Indo-European *h₁ogʷʰis[8]). Latin had the name stellio for a type of spotted newt, now used for species of the Stellagama genus. Ancient Greek had the name κορδύλος, presumably for the water newt (immature newt, eft).[9] German has Molch, from Middle High German mol, wikt:olm, like the English term of unknown etymology.

Newts are also known as Tritones (viz., named for the mythological Triton) in historical literature, and "triton" remains in use as common name in some Romance languages, in Greek, and in Russian. The systematic name Tritones was introduced alongside Pleurodelinae by Tschudi in 1838, based on the type genus named Triton by Laurenti in 1768. Laurenti's Triton was renamed to Triturus ("Triton-tail") by Rafinesque in 1815.[10] Tschudi's Pleurodelinae is based on the type genus Pleurodeles (ribbed newt) named by Michahelles in 1830 (the name meaning "having prominent ribs", formed from πλευρά "ribs" and δῆλος "conspicuous").


The three common European genera are the crested newts (Triturus spp.), the smooth and palmate newts (Lissotriton spp.), and the banded newts (Ommatotriton spp.). Other species present in Europe are the Iberian ribbed newt (Plurodeles waltl), which is the largest of the European newts,[11] the Pyrenean brook newt (Calotriton sp.); the European brook newt (Euproctus spp.) and the alpine newt (Ichtyosaura alpestris).[12][13]

In North America, the eastern newts (Notophthalmus spp.) include the red-spotted newt (Notophthalmus viridescens), which is the most abundant species, but it is limited to the area east of the Rocky Mountains. The three species of coastal or western newts are the red-bellied newt, the California newt, and the rough-skinned newt, all of which belong to the genus Taricha, which is confined to the area west of the Rockies.[citation needed]

In Southeast Asia and Japan, species commonly encountered in the pet trade include the fire belly newts (Cynops spp. and Hypselotriton spp.), the paddle-tail newts (Pachytriton spp.), the crocodile newts (Tylototriton spp.), and the warty newts (Paramesotriton spp.). In the Middle East are the spotted newts (Neurergus spp.).[14]


A red-spotted newt (eft stage) is showing bright aposematic colouration to warn predators of its highly toxic skin.[15]

Newts share many of the characteristics of their salamander kin, Caudata, including semipermeable glandular skin, four equal-sized limbs, and a distinct tail. The newt's skin, however, is not as smooth as that of other salamanders.[16] Aquatic larvae have true teeth on both upper and lower jaws, and external gills.[17] They have the ability to regenerate limbs, eyes, spinal cords, hearts, intestines, and upper and lower jaws. The Japanese fire belly newt can regenerate its eye lens 18 times over a period of 16 years and retain its structural and functional properties.[18] The cells at the site of the injury have the ability to undifferentiate, reproduce rapidly, and differentiate again to create a new limb or organ. One hypothesis is that the undifferentiated cells are related to tumour cells, since chemicals that produce tumours in other animals will produce additional limbs in newts.[19]


Alpine newt larva part-way through metamorphosis

The main breeding season for newts is (in the Northern Hemisphere) in June and July. After courtship rituals of varying complexity, which take place in ponds or slow-moving streams, the male newt transfers a spermatophore, which is taken up by the female. Fertilized eggs are laid singly and are usually attached to aquatic plants.[citation needed] This distinguishes them from the free-floating eggs of frogs or toads, which are laid in clumps or in strings. Plant leaves are usually folded over and attached to the eggs to protect them. The tadpoles, which resemble fish fry but are distinguished by their feathery external gills, hatch out in about three weeks. After hatching, they eat algae, small invertebrates, or other tadpoles.[citation needed]

During the subsequent few months, the tadpoles undergo metamorphosis, during which they develop legs, and the gills are absorbed and replaced by air-breathing lungs.[20] Some species, such as the North American newts, also become more brightly coloured during this phase. Once fully metamorphosised, they leave the water and live a terrestrial life, when they are known as "efts".[21] Only when the eft reaches adulthood will the North American species return to live in water, rarely venturing back onto the land. Conversely, most European species live their adult lives on land and only visit water to breed.[22]


Taricha newts are known for their toxicity

Many newts produce toxins in their skin secretions as a defence mechanism against predators. Taricha newts of western North America are particularly toxic. The rough-skinned newt Taricha granulosa of the Pacific Northwest produces more than enough tetrodotoxin to kill an adult human, and some Native Americans of the Pacific Northwest used the toxin to poison their enemies.[23] However, the toxins are only dangerous if ingested, and the newts can easily and safely live in the same ponds or streams as frogs and other amphibians, or be safely kept as pets. The only predators of Taricha newts are garter snakes, some having developed a resistance to the poison. Most newts can be safely handled, provided the toxins they produce are not ingested or allowed to come in contact with mucous membranes or breaks in the skin.[23] After handling, proper hand-washing techniques should be followed due to the risk from the toxins they produce and bacteria they carry, such as Salmonella.[24][25] It is, however, illegal to handle or disturb great crested newts in the UK without a licence.[26]


Newts form one of three subfamilies in the Salamandridae family, aside Salamandrinae and Salamandrininae.[27] They comprise most extant species in the family, roughly 100, which are classified in fourteen genera:[28]

Hypselotriton, Laotriton and Liangshantriton are regarded as separate genera by some authors, but this is not unanimous.[28]

The term "newt" has traditionally been seen as an exclusively functional term for salamanders living in water, and not a clade. Phylogenetic analyses have however shown that species in the Salamandridae traditionally called newts do form a monophyletic group.[1][27][28] Other, more distantly related salamander families also contain fully or in part aquatic species, such as the mole salamanders, the Proteidae, or the Sirenidae.

Phylogenetic analyses estimated the origin of the newt subfamily in the Late Cretaceous to Eocene.[1] Several fossil salamanders have also been referred to the Pleurodelinae, including:[29]

Conservation status[edit]


The Yunnan lake newt is considered extinct.[30]


Some newt populations in Europe have decreased because of pollution or destruction of their breeding sites and terrestrial habitats, and countries such as the UK have taken steps to halt their declines.[31][32] In the UK, they are protected under the Wildlife and Countryside Act 1981 and the Habitat Regulations Act 1994. It is illegal to catch, possess, or handle great crested newts without a licence, or to cause them harm or death, or to disturb their habitat in any way. The IUCN Red List categorises the species as ‘lower risk’[22][26] Although the other UK species, the smooth newt and palmate newt are not listed, the sale of either species is prohibited under the Wildlife and Countryside Act, 1981.[33]

In Europe, nine newts are listed as "strictly protected fauna species" under appendix II of the Convention on the Conservation of European Wildlife and Natural Habitats:[34]

The remaining European species are listed as "protected fauna species" under appendix III.[35]

As bioindicators[edit]

Newts, as with salamanders in general and other amphibians, serve as bioindicators because of their thin, sensitive skin and evidence of their presence (or absence) can serve as an indicator of the health of the environment. Most species are highly sensitive to subtle changes in the pH level of the streams and lakes where they live. Because their skin is permeable to water, they absorb oxygen and other substances they need through their skin. Scientists study the stability of the amphibian population when studying the water quality of a particular body of water.[citation needed]

As pets[edit]

Chinese warty newts, Chinese fire belly newts, eastern newts, paddletail newts, Japanese fire belly newts, Chuxiong fire-bellied newts, Triturus species, emperor newts, Spanish ribbed newts (leucistic genes exist), and red-tailed knobby newts are some commonly seen newts in the pet trade. Some newts rarely seen in the pet trade are Rough-skinned newts, Kaiser's spotted newts, Banded newts and Yellow-spotted newts.


  1. ^ a b c Zhang, Peng; Papenfuss, Theodore J.; Wake, Marvalee H.; Qu, Lianghu; Wake, David B. (2008). "Phylogeny and biogeography of the family Salamandridae (Amphibia: Caudata) inferred from complete mitochondrial genomes" (PDF). Molecular Phylogenetics and Evolution. 49 (2): 586–597. doi:10.1016/j.ympev.2008.08.020. ISSN 1055-7903. 
  2. ^ "Newt". Merriam-Webster Dictionary. Encylopaedia Britannica. Retrieved 2015-06-24. 
  3. ^ Brockes, J; Kumar, A (Jan 2005). "Newts". Current Biology. 15 (2): R42–R44. doi:10.1016/j.cub.2004.12.049. PMID 15668151. Retrieved 2013-06-06. 
  4. ^ Oxford English Dictionary; Anon. "Online etymological dictionary". Douglas Harper. Retrieved 9 October 2013. 
  5. ^ The Gentleman's Magazine, and Historical Chronicle, Volume 47 (1777), p. 321.
  6. ^ John Wilkins, An Essay Towards a Real Character, and a Philosophical Language (1668), p. 161. "the water-eft, or newt, is only the larva of the land-eft, as tadpoles are of frogs." Gilbert White, The Natural History and Antiquities of Selborne, in the County of Southampton (1789) p. 50. "the salamandra aquatica of Hay, (the water-newt, or eft,)" Archibald Constable, Constable's miscellany of original and selected publications in the various departments of literature, science, & the arts, Volume 45 (1829), p. 63.
  7. ^ John Jamieson, An etmological dictionary of the Scottish language (1818)
  8. ^ Wolfgang Pfeifer (ed.), Etymologisches Wörterbuch des Deutschen. Deutscher Taschenbuch Verlag, Munich 1997 (revised edition of Akademie Verlag, Munich 1989 and 1993), p. 265, s.v. Eidechse. Pfeifer gives the second element as germ. *þahsjō(n), relating it to Middle High German dehse "distaff", so that both animals (lizard and badger) were parallelized due to their common, spindle-shaped bodies.
  9. ^ Henry George Liddell, Robert Scott, A Greek-English Lexicon
  10. ^ Alain Dubois and Roger Bour, The nomenclatural status of the nomina of amphibians and reptiles created by Garsault (1764), with a parsimonious solution to an old nomenclatural problem regarding the genus Bufo (Amphibia, Anura), comments on the taxonomy of this genus, and comments on some nomina created by Laurenti (1768), Zootaxa 2447 (2010), 1–52.
  11. ^ "A Newt Tale". Retrieved 2013-06-06. 
  12. ^ Steinfartz, S., S. Vicario, J. W. Arntzen, & A. Caccone (2006): A Bayesian approach on molecules and behavior: reconsidering phylogenetic and evolutionary patterns of the Salamandridae with emphasis on Triturus newts. Journal of Experimental Zoology Part B: Molecular and Developmental Evolution
  13. ^ Carranza, S. & Amat, F. (2005) Taxonomy, biogeography and evolution of Euproctus (Amphibia: Salamandridae), with the resurrection of the genus Calotriton and the description of a new endemic species from the Iberian Peninsula, Zoological Journal of the Linnean Society 145 (4), 555–582.
  14. ^ "Welcome -". Retrieved 2013-06-06. 
  15. ^ "Newt Information and Gallery". Retrieved 2013-06-06. 
  16. ^ Collins, J. T.; Conant, R.; Stebbins, R. C.; Peterson, R. T. (1999). Peterson First Guide to Reptiles and Amphibians. Houghton Mifflin Harcourt. ISBN 0-395-97195-0. 
  17. ^ Heying, Heather. "Adw: Caudata: Information". Retrieved 2013-06-06. 
  18. ^ "Newts re-grow eye lens 18 times over". COSMOS magazine. 2011-07-13. Retrieved 2013-06-06. 
  19. ^ [1] Archived September 2, 2006, at the Wayback Machine.
  20. ^ "Amphibians - body, used, water, process, Earth, life, characteristics, form, animals, oxygen, air, plant, change, History, Characteristics, Life cycle, Three major groupings". 2009-10-13. Retrieved 2013-06-06. 
  21. ^ "Cambridge City Council: Local Nature Reserves". 2005-07-25. Retrieved 2013-06-06. 
  22. ^ a b "BBC Nature - Great crested newt videos, news and facts". Retrieved 2013-06-06. 
  23. ^ a b "Caudata Culture Articles - Newt Toxins". Retrieved 2013-06-06. 
  24. ^ Salmonellosis - Reptiles and Amphibians
  25. ^ "CDC MMWR: Reptile-Associated Salmonellosis: Selected States, 1998-2002". 2003-12-12. Retrieved 2013-06-06. 
  26. ^ a b "Science & Nature - Wildfacts - Smooth newt, common newt". BBC. 2012-04-27. Retrieved 2013-06-06. 
  27. ^ a b Pyron, R.A.; Weins, J.J. (2011). "A large-scale phylogeny of Amphibia including over 2800 species, and a revised classification of advanced frogs, salamanders, and caecilians" (PDF). Molecular Phylogenetics and Evolution. 61 (2): 543–853. doi:10.1016/j.ympev.2011.06.012. PMID 21723399. 
  28. ^ a b c Frost, D.R. (2016). "Pleurodelinae. Amphibian Species of the World: an Online Reference. Version 6.0". New York: American Museum of Natural History. Retrieved 2016-08-27. 
  29. ^ Marjanović, David; Witzmann, Florian (2015). "An Extremely Peramorphic Newt (Urodela: Salamandridae: Pleurodelini) from the Latest Oligocene of Germany, and a New Phylogenetic Analysis of Extant and Extinct Salamandrids". PLOS ONE. 10 (9): e0137068. doi:10.1371/journal.pone.0137068. ISSN 1932-6203.  open access publication - free to read
  30. ^ Yang Datong, Michael Wai Neng Lau (2004). "Cynops wolterstorffi". IUCN Red List of Threatened Species. Version 2012.2. International Union for Conservation of Nature. Retrieved 1 January 2013. 
  31. ^ "USGS Amphibian Research Monitoring Initiative (Pacific Northwest Region)". 2013-01-30. Retrieved 2013-06-06. 
  32. ^ UK Biodiversity Action Plan Archived October 24, 2007, at the Wayback Machine.
  33. ^ "Smooth newt videos, photos and facts - Triturus vulgaris". ARKive. Retrieved 2013-06-06. 
  34. ^ "Annexe II: Strictly protected fauna species". Retrieved 2013-06-06. 
  35. ^ "Annexe III: Protected fauna species". Retrieved 2013-06-06. 

External links[edit]