View source for Danube crested newt

{{Short description|Species of amphibian}}
{{Speciesbox
| name = Danube crested newt
| image = Triturus_dobrogicus.jpg
| status = LC 
| status_system = IUCN3.1
| status_ref = <ref name="iucn status">{{cite iucn |author=Amphibian Specialist Group |date=2022 |title=''Triturus dobrogicus'' |page=e.T22216A89709283 |doi=10.2305/IUCN.UK.2022.RLTS.T22216A89709283.en |access-date=27 July 2022}}</ref>
| genus = Triturus
| species = dobrogicus
| authority = (Kiritzescu, 1903)
| range_map = Triturus_dobrogicus_distribution.svg
| synonyms_ref = <ref name="amphibian-species-world"/>
| synonyms = {{hidden begin}}
* ''Triton cristatus'' var. ''dobrogicus'' <small>Kiritzescu, 1903</small>
* ''Molge macrosoma'' <small>Boulenger, 1908</small>
* ''Triton cristatus danubialis'' <small>Wolterstorff, 1923</small>
* ''Triton cristatus cristatus'' forma ''dobrogica'' <small>Wolterstorff, 1923</small>
* ''Triton cristatus danubialis'' forma ''werneri'' <small>Wolterstorff, 1923</small>
* ''Triturus cristatus danubialis'' <small>Mertens, 1923</small>
* ''Triton'' (''Neotriton'') ''cristatus danubialis'' <small>Bolkay, 1928</small>
* ''Triturus cristatus dobrogicus'' <small>Mertens & Müller, 1928</small>
* ''Molge cristata danubialis'' forma ''smederevana'' <small>Karaman, 1948</small>
* ''Triturus cristatus danubialis'' var. ''intermedia'' <small>Fuhn, 1953</small>
* ''Triturus cristatus dobrogicus'' <small>Mertens & Wermuth, 1960</small>
* ''Triturus dobrogicus'' <small>Bucci-Innocenti, Ragghianti & Mancino, 1983</small>
* ''Triturus'' (''Triturus'') ''dobrogicus'' <small>MacGregor, Sessions & Arntzen, 1990</small>
* ''Triturus dobrogicus dobrogicus'' <small>Litvinchuk and Borkin, 2000</small>
* ''Triturus dobrogicus macrosomus'' <small>Litvinchuk and Borkin, 2000</small>
* ''Triturus'' (''Triturus'') ''dobrogicus dobrogicus'' <small>Dubois & Raffaëlli, 2009</small>
* ''Triturus'' (''Triturus'') ''dobrogicus macrosoma'' <small>Dubois & Raffaëlli, 2009</small>
{{hidden end}}
}}

The '''Danube crested newt''' or '''Danube newt''' ('''''Triturus dobrogicus''''') is a species of [[newt]] found in central and eastern Europe, along the basin of the [[Danube]] river and some of its tributaries and in the [[Dnieper]] delta. It has a smaller and more slender body than the other crested newts in genus ''[[Triturus]]'' but like these, males develop a conspicuous jagged seam on back and tail during breeding season.

For half of the year or longer, adults live in slow-flowing river margins, lakes, or ponds, where reproduction takes place. Males perform a [[courtship display]], and females lay around 200 eggs individually onto leaves of aquatic plants. Larvae develop two to four months in the water before reaching [[metamorphosis]]. For the remainder of the year, the newts live in shady land habitats, usually forests. Although not yet considered threatened, Danube crested newt populations have declined significantly, the reason being mainly [[habitat loss]]. The species is protected by law in the European Union.

==Taxonomy==

The Danube crested newt was described as a variety of the [[northern crested newt]] (''Triturus cristatus'') by C. Kiritzescu in 1903.<ref name="Kiritzescu1903"/> Later, it was considered a [[subspecies]] until genetic analysis supported its recognition as a separate species in the crested newt [[species complex]].<ref name="amphibian-species-world"/> The northern crested newt is its [[sister species]], according to [[phylogenomic]] studies.<ref name="WielstraArntzen2011"/><ref name="WielstraMcCartney-Melstad2019"/>

Separated populations from the [[Danube Delta]] and the [[Pannonian Basin]] (see section ''Distribution and habitats'') were described as two subspecies, ''T.&nbsp;dobrogicus dobrogicus'' and ''T.&nbsp;dobrogicus macrosoma'', in 2000.<ref name="LitvinchukBorkin2000"/> Later genetic study, however, did not support the distinction of these two forms.<ref name="VörösArntzen2010"/><ref name="WielstraArntzen2016"/>

{{Annotated image
| image = Wielstra2019 Triturus Graphical Abstract blank.jpg
| width = 300
| image-width = 300
| float = right
| annotations =
{{Annotation|34|28|marbled<br />newts|font-size=13}}
{{Annotation|2|155|crested<br />newts|font-size=13|text-align=right}}
{{Annotation|140|40|''[[Triturus marmoratus|T. marmoratus]]'' and<br />''[[Triturus pygmaeus|T. pygmaeus]]''|font-size=13}}
{{Annotation|140|110|''[[Triturus karelinii|T. karelinii]]'', ''[[Triturus anatolicus|T. anatolicus]]''<br />and ''[[Triturus ivanbureschi|T. ivanbureschi]]''|font-size=13}}
{{Annotation|140|180|''[[Triturus carnifex|T. carnifex]]'' and<br />''[[Triturus macedonicus|T. macedonicus]]''|font-size=13}}
{{Annotation|140|250|''[[Triturus cristatus|T. cristatus]]''|font-size=13}}
{{Annotation|140|310|'''''T. dobrogicus'''''|font-size=13}}
| caption = Position of the Danube crested newt (''T. dobrogicus'') in the [[phylogenetic tree]] of the genus ''Triturus''<ref name="WielstraMcCartney-Melstad2019"/>
}}

==Description==

Measuring {{convert|13|to|15|cm|in}} long in total, sometimes up to {{convert|18|cm|in}} in females,<ref name="Sparreboom2014"/>{{rp|345}} the Danube crested newt is the smallest crested newt species. It has a more slender, elongate body than the other species, well adapted to swimming, with a narrow head and relatively short limbs. This body shape has evolved through an increase in the number of [[rib]]-bearing [[vertebrae]]: there are 16–17 of them in ''T.&nbsp;dobrogicus'', the highest number among the crested newts.<ref name="JehleThiesmeier2011"/>{{rp|10–14}}

The Danube crested newt's back and sides are dark brown with black spots and white stippling. The belly is orange to red (in other crested newts, it is usually yellow or orange–yellow), with small or medium-sized black blotches that have sharp edges. Like all crested newts, ''T.&nbsp;dobrogicus'' males develop a crest on their back and tail during breeding phase, which can be quite high and jagged, usually starts between the eyes and nostrils, and is interrupted at the tail base. Another feature of males at breeding season is a bluish-white stripe along the tail.<ref name="JehleThiesmeier2011"/>{{rp|10–14}}<ref name="Sparreboom2014"/>{{rp|345}} Females can sometimes have a yellow stripe along the back, similar to the [[Italian crested newt]] (''T. carnifex'').<ref name="Sparreboom2014"/>{{rp|345}}

==Distribution and habitats==
The Danube crested newt is found in three [[allopatric]] areas of distribution from central to eastern Europe:
*''Pannonian basin'': From easternmost [[Austria]] through [[Czech Republic]] (small part in the southeast), [[Slovakia]], Hungary, nordeast [[Slovenia]] (river Mura backwaters<ref>{{cite web | url=https://www.ckff.si/icvds/vrste-dvozivk/triturus-dobrogicus | title=Informacijski center za varstvo dvoživk Slovenije }}</ref>), northern [[Croatia]], [[Bosnia-Hercegovina]] (marginally), northern [[Serbia]] to the east of [[Romania]] and southeast of [[Ukraine]] ([[Zakarpattia Oblast|Transcarpathian region]]). This includes the middle floodplains of the [[Danube]] river and some of its tributaries, including the [[Drava]], [[Sava]] and [[Tisza]].<ref name="VörösArntzen2010"/>
*''Lower Danube and Danube delta'': Separated from the Pannonian basin by an area where the northern crested newt occurs, this central part ranges from southern Romania, northern [[Bulgaria]], and small parts of southern [[Moldova]] to the [[Odesa region]] of southern Ukraine.<ref name="VörösArntzen2010"/>
*''[[Dnieper]] delta'': This small area of distribution in southern Ukraine was reported in 2005. It is now isolated by [[steppe]] from the Danube basin, but it has been suggested that these areas were connected through [[marshlands]] during the [[last glacial maximum]], when the level of the [[Black Sea]] was around 100 metres lower than today. This range may also extend to the lower basins of the [[Dniester]] and [[Bug River|Bug]] rivers.<ref name="Litvinchuk2005"/>

[[File:NPDonauAuen.jpg|thumb|upright=1.15|right|alt=An oxbow lake surrounded by trees.|The [[riparian forest]]s of [[Danube-Auen National Park]] in Austria harbour important populations, breeding in a variety of temporarily flooded water bodies.<ref name="Gollmann2009"/>]]

In addition to the northern crested newt to the north, the Danube crested newt's range borders that of the Italian crested newt (''T.&nbsp;carnifex'') in the west, and that of the [[Macedonian crested newt|Macedonian]] (''T.&nbsp;macedonicus'') and [[Balkan crested newt|Balkan]] (''T.&nbsp;ivanbureschi'') crested newts in the south.<ref name="JehleThiesmeier2011"/>{{rp|16–17}}

Compared to the other crested newt species, the Danube crested newt is more adapted to life along a river system and frequently occurs in flowing water and together with fish. Typical breeding sites are slow-flowing river margins, [[oxbow lakes]], flooded [[marshland]], larger ponds, or ditches, provided abundant underwater vegetation is available.<ref name="JehleThiesmeier2011"/>{{rp|44–48}}<ref name="Griffiths1996"/>{{rp|144–145}} During land phase, the newts live in deciduous forests or groves, bushlands, or meadows.<ref name="iucn status"/>

==Lifecycle and behaviour==
{{see also|Triturus#Lifecycle and behaviour}}
Danube crested newts have the longest aquatic phase in the genus ''Triturus''. Adults move to their breeding sites in February or March and usually stay there for six months; occasionally, they may even stay longer or return to the water in autumn.<ref name="JehleThiesmeier2011"/>{{rp|44}}<ref name="Griffiths1996"/>{{rp|144–145}} Males court females with a [[courtship display|display]] of ritualised body movements. When they have gained the female's interest, they guide it over a [[spermatophore]] they deposit on the ground, which the female then takes up with her [[cloaca]].<ref name="JehleThiesmeier2011"/>{{rp|80–89}} The eggs are fertilised internally. As in other crested newts, a female lays around 200 eggs per season, which are folded individually into leaves of aquatic plants. Eggs and larvae are smaller than in the other crested newt species, and they take longer (two to four months) until they reach [[metamorphosis]] and leave the water.<ref name="JehleThiesmeier2011"/>{{rp|61–65}}<ref name="Sparreboom2014"/>{{rp|345}}

Both in water and on land, the newts are largely nocturnal. In their aquatic habitats, they hide under vegetation, and on land, they use structures such as logs, rocks, or small animal burrows for cover.<ref name="JehleThiesmeier2011"/>{{rp|47–48,58}} They feed mainly on different [[invertebrates]], but in the water may also prey on [[tadpole]]s and smaller newts.<ref name="JehleThiesmeier2011"/>{{rp|58–59}} Predators include [[herons]] and other birds, snakes such as the [[grass snake]], and various carnivorous mammals.<ref name="JehleThiesmeier2011"/>{{rp|78}}

==Threats and conservation==
{{see also|Triturus#Threats and conservation}}
The population of the Danube crested newt has declined significantly, and the [[International Union for Conservation of Nature]] has assessed its conservation status as "[[least concern]]". The main threat is [[habitat destruction]] by humans, especially through drainage, damming, or pollution. [[Hybridisation (biology)|Hybridisation]] with other crested newt species and a loss of breeding ponds because of decreasing spring rain in the southern range (possibly due to [[global warming]]) are also seen as threats.<ref name="iucn status"/> Like the other crested newts, ''T.&nbsp;dobrogicus'' is listed in the [[Berne Convention on the Conservation of European Wildlife and Natural Habitats|Berne Convention]] (appendix II) and the EU [[Habitats Directive]] (annexes II and IV), and capture, disturbance, killing, trade, and destruction of habitats are prohibited.<ref name="bern-convention"/><ref name="habitats-directive"/>

==See also==
{{Portal|Amphibians and Reptiles}}
* [[List of amphibians of Europe]]

==References==
{{Reflist|30em|refs=

<ref name="amphibian-species-world">{{cite web |last1=Frost |first1=D.R. |title=''Triturus dobrogicus'' (Kiritzescu, 1903). Amphibian Species of the World: an Online Reference. Version 6.0 |year=2015 |publisher=American Museum of Natural History |location=New York, USA |url=http://research.amnh.org/vz/herpetology/amphibia/index.php//Amphibia/Caudata/Salamandridae/Pleurodelinae/Triturus/Triturus-dobrogicus |access-date=2015-07-11}}</ref>

<ref name="bern-convention">{{cite web |title=Convention on the Conservation of European Wildlife and Natural Habitats |year=1979 |publisher=Council of Europe |location=Bern |url=http://conventions.coe.int/treaty/en/Treaties/Html/104.htm |access-date=2015-05-24}}</ref>

<ref name="Gollmann2009">{{Cite report |last1=Gollmann |first1=G. |last2=Pintar |first2=M. |year=2009 |title=Erhebung des Donaukammmolches (''Triturus dobrogicus'') in der Lobau [Assessment of the Danube crested newt (''Triturus dobrogicus'') in the Lobau floodplain] |url=https://www.wien.gv.at/kontakte/ma22/studien/pdf/donaukammmolch.pdf |publisher=University of Natural Resources and Applied Life Sciences, Vienna |language=de}}</ref>

<ref name="Griffiths1996">{{cite book |last1=Griffiths |first1=R.A. |title=Newts and salamanders of Europe |year=1996 |publisher=Poyser |location=London, UK |isbn=0-85661-100-X}}</ref>

<ref name="habitats-directive">{{cite act |title=Council directive 92/43/EEC on the conservation of natural habitats and of wild fauna and flora |number=1992L0043 |date=1 January 2007 |url=http://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:01992L0043-20070101 |access-date=2015-05-31}}</ref>

<ref name="JehleThiesmeier2011">{{cite book |last1=Jehle |first1=R.|last2=Thiesmeier |first2=B. |last3=Foster |first3=J. |title=The crested newt. A dwindling pond dweller |year=2011 |publisher=Laurenti Verlag |location=Bielefeld, Germany |isbn=978-3-933066-44-2}}</ref>

<ref name="Kiritzescu1903">{{cite journal |last1=Kiritzescu |first1=C. |title=Contributions à la faune des batraciens de Roumanie |year=1903 |journal=Buletinul Societatii de Sciinte Din Bucuresci, România |volume=12 |pages=243–265 |language=fr}}</ref>

<ref name="Litvinchuk2005">{{cite journal |last1=Litvinchuk |first1=S.N. |title=A Record of the Danube Newt, ''Triturus dobrogicus'', from the Dnepr River Delta (Ukraine) |year=2005 |journal=Russian Journal of Herpetology |volume=12 |issue=1 |pages=69–72 |url=http://rjh.folium.ru/index.php/rjh/article/view/683 }}</ref>

<ref name="LitvinchukBorkin2000">{{cite journal |last1=Litvinchuk |first1=S.N.|last2=Borkin |first2=L.N. |title=Intraspecific taxonomy and nomenclature of the Danube crested newt, ''Triturus dobrogicus'' |year=2000 |journal=Amphibia-Reptilia |volume=21 |issue=4 |pages=419–430 |url=http://www.caudata.org/forum/attachments/f1173-advanced-newt-salamander-topics/f30-species-genus-family-discussions/f32-eurasian-newts-triturus-former-triturus-calotriton-euproctus/14104d1297113263-t-dobrogicus-macrosomus-courtship-breeding-photos-intraspecific-taxonomy-nomenclature-danube-crested-newt-triturus-dobrogicus.pdf |doi=10.1163/156853800300059313}}</ref>

<ref name="Sparreboom2014">{{cite book | last = Sparreboom | first = M. |year = 2014 | title = Salamanders of the Old World: The Salamanders of Europe, Asia and Northern Africa | isbn = 9789004285620 | publisher = KNNV Publishing | location = Zeist, The Netherlands | doi = 10.1163/9789004285620 }}</ref>

<ref name="VörösArntzen2010">{{cite journal |last1=Vörös |first1=J. |last2=Arnzten |first2=J.W. |title=Weak population structuring in the Danube crested newt, ''Triturus dobrogicus'', inferred from allozymes |year=2000 |journal=Amphibia-Reptilia |volume=31 |issue=3 |pages=339–346 |doi=10.1163/156853810791769518 |url=https://www.researchgate.net/publication/233574302 |format=PDF}}</ref>

<ref name="WielstraArntzen2011">{{cite journal |last1=Wielstra |first1=B. |last2=Arntzen |first2=J.W. |title=Unraveling the rapid radiation of crested newts (''Triturus cristatus'' superspecies) using complete mitogenomic sequences |journal=BMC Evolutionary Biology |volume=11 |issue=1 |year=2011 |pages=162 |issn=1471-2148 |doi=10.1186/1471-2148-11-162 |pmid=21672214 |pmc=3224112 |doi-access=free |bibcode=2011BMCEE..11..162W }}</ref>

<ref name="WielstraArntzen2016">{{cite journal |last1=Wielstra |first1=B. |last2=Arntzen |first2=J.W. |last3=Vörös |first3=J. |title=Is the Danube crested newt ''Triturus dobrogicus'' polytypic? A review and new nuclear DNA data |journal=Amphibia-Reptilia |volume=37 |issue=2 |year=2016 |pages=167–177 |issn=0173-5373 |doi=10.1163/15685381-00003041|s2cid=88449169 |url=http://eprints.whiterose.ac.uk/104514/3/Wielstra%20AR%202016.pdf }}</ref>

<ref name="WielstraMcCartney-Melstad2019">{{cite journal |last1=Wielstra |first1=B. |last2=McCartney-Melstad |first2=E. |last3=Arntzen |first3=J.W. |last4=Butlin |first4=R.K. |last5=Shaffer |first5=H.B. |title=Phylogenomics of the adaptive radiation of ''Triturus'' newts supports gradual ecological niche expansion towards an incrementally aquatic lifestyle |journal=Molecular Phylogenetics and Evolution |volume=133 |year=2019 |pages=120–127 |issn=1055-7903 |doi=10.1016/j.ympev.2018.12.032 |pmid=30630099 |doi-access=free|bibcode=2019MolPE.133..120W |hdl=1887/73405 |hdl-access=free }}</ref>

}}

==External links==
{{Wikispecies|Triturus dobrogicus|Danube crested newt}}
*[http://amphibiaweb.org/cgi/amphib_query?where-genus=Triturus&where-species=dobrogicus AmphibiaWeb - ''Triturus dobrogicus'']
*{{ARKive}}

{{Triturus-species}}
{{Taxonbar|from=Q253442}}
{{Good article}}

[[Category:Triturus]]
[[Category:Amphibians described in 1903]]
[[Category:Amphibians of Europe]]
[[Category:Taxonomy articles created by Polbot]]
[[Category:Habitats Directive species]]