View source for Ladder snake

{{Short description|Species of snake}}
{{Speciesbox
| name = Ladder snake
| image = Rhinechis scalaris cropped.jpg
| status = LC
| status_system = IUCN3.1
| status_ref = <ref name="iucn status 15 November 2021">{{cite iucn |author=Pleguezuelos, Juan M. |author-link=species:Juan Manuel Pleguezuelos |author2=Sá-Sousa, Paulo |author2-link=species:Paulo Sá-Sousa |author3=Pérez-Mellado, Valentin |author3-link=species:Valentín Pérez-Mellado |author4=Marquez, Rafael |author4-link=species:Rafael Márquez |author5=Cheylan, Marc |author5-link=species:Marc Cheylan |author6=Corti, Claudia |author6-link=species:Claudia Corti |author7=Martínez-Solano, Iñigo |author7-link=species:Iñigo Martínez-Solano |date=2009 |title=''Zamenis scalaris'' |volume=2009 |page=e.T61565A12516902 |doi=10.2305/IUCN.UK.2009.RLTS.T61565A12516902.en |access-date=15 November 2021}}</ref>
| genus = Zamenis
| species = scalaris
| authority = ([[Heinrich Rudolf Schinz|Schinz]], 1822)
| range_map = Rhinechis_scalaris_dis.png
| range_map_caption = Range map
| synonyms = *''Coluber scalaris'' <br/>{{small|Schinz, 1822}}
*''Xenodon michahelles'' <br/>{{small|[[Hermann Schlegel|Schlegel]], 1837}}
*''Rhinechis scalaris'' <br/>{{small|— [[André Marie Constant Duméril|A.M.C. Duméril]], [[Gabriel Bibron|Bibron]] & <br/>[[Auguste Duméril|A.H.A. Duméril]], 1854}}
*''Elaphe scalaris'' <br/>{{small|— [[Burkard Kahl|Kahl]] et al., 1980}}
*''Zamenis scalaris'' <br/>{{small|— [[species:Hussam Zaher|Zaher]] et al., 2012}}
| synonyms_ref =<ref>{{EMBL species|genus=Zamenis|species=scalaris}} www.reptile-database.org.</ref>
}}

The '''ladder snake''' ('''''Zamenis scalaris''''') is a [[species]] of non-venomous [[snake]] in the [[Family (biology)|family]] [[Colubridae]]. The species is [[Endemism|endemic]] to southwestern [[Europe]].

==Distribution==
The geographic range of the ladder snake includes [[Portugal]], [[Spain]], southern [[France]] and just into [[Italy]], also [[Menorca]] and the [[Iles d'Hyères]] off [[Provence]], but it is absent from northern [[Iberia]] including much of the [[Pyrenees]], [[Galicia (Spain)|Galicia]] (although the species is found on [[Ons Island]], in the [[Atlantic Islands of Galicia National Park]]<ref>[http://www.magrama.gob.es/es/red-parques-nacionales/nuestros-parques/islas-atlanticas/visita-virtual/fauna/culebra-de-escalera.aspx "''Culebra de escalera'' (''Elaphe scalaris'')"] {{Webarchive|url=https://web.archive.org/web/20150419021127/http://www.magrama.gob.es/es/red-parques-nacionales/nuestros-parques/islas-atlanticas/visita-virtual/fauna/culebra-de-escalera.aspx |date=2015-04-19 }}[[Ministerio de Agricultura, Alimentación y Medio Ambiente]]. Retrieved 10 April 2014. {{in lang|es}}.</ref>), [[Cantabria]] and the [[Basque Country (autonomous community)|Basque Country]].<ref name = "Wildlist"/>  The population on Menorca may stem from an introduction by humans.<ref name="iucn status 15 November 2021" />

==Habitat==
The ladder snake enjoys scrub bushy cover, including orchards, vineyards, hedges and overgrown dry-stone walls; it is common in the [[maquis shrubland|maquis]]. Habitats with stones and boulders and low shade are preferred. Although known at altitudes over {{convert|2000|m}}, this is a species which prefers altitudes from sea level to {{convert|700|m}}.<ref name = "Wildlist"/>

==Description==
The ladder snake is a medium-sized snake which reaches a maximum total length (including tail) of around {{convert|160|cm|in|abbr=on}} but which averages {{convert|120|cm|in|abbr=on}}. It has a pointed snout.  As an adult the ladder snake is less variable than many related snake species, the basic colour goes from yellowish to dark brown,  with two darker stripes running down the length of the body from neck to tail. It normally also has a dark stripe running from the rear of the eye to the angle of the jaw and sometime subtle, darker markings on the sides. The ventral side is pale, varying from a silvery-grey to whitish, with the occasional dark spot. The eye is dark. The juvenile snakes have lighter and brighter colouration, varying from yellow to light brown, with the characteristic “ladder” pattern picked out in black along the upperside. The pale underside has black markings which sometimes coalesce to cover the whole of the underside. As the snake ages these colours and patterns fade until the simpler adult pattern is left.<ref name = "Wildlist"/>

==Diet==
Like other “rat snakes”, the majority of the ladder snake’s [[Predation|prey]] is mammals such as mice, rabbits and shrews, making up 75% of prey items with a further quarter being spiders, insects (especially grasshoppers) and a few birds. To prey on birds the ladder snake will climb to search for active nests in trees or on man-made structures. Lizards are also eaten. Juvenile ladder snakes prefer small lizards, baby rodents, spiders, and grasshoppers.<ref name = "Wildlist"/>

==Behaviour==
The ladder snake is normally active by day, but during the hottest summer months it may be [[nocturnal]], while in the spring months it may be more [[crepuscular]]. Its behaviour is said to be more like that of [[whipsnakes]] rather than that of [[rat snake]]s. It is more aggressive and defensive than most of the species formerly classified alongside it in the [[genus]] ''[[Elaphe]]''. Defensive signals include hissing and lunging forward with the mouth open. Any attempt to pick up a ladder snake may be greeted by sharp bites and also the emptying of the cloacal glands, releasing an offensive odour.<ref name = "Wildlist"/>

It is a more mobile snake than many of its relatives and movements of up to 100 m per day have been recorded, while the average home territory of an individual is 4,500 m<sup>2</sup>. Adults may enter barns or similar buildings in search of rodent prey, but they do not normally use such places for shelter and prefer rodent burrows, piles of stones or hollow trees.<ref name = "Wildlist"/>

==Breeding==
In Iberia ladder snake courtship occurs during May and June, however some females do not breed every year. Copulation lasts around an hour, and a [[Clutch (eggs)|clutch]] with an average size of 15 eggs (varies between 4 and 24 eggs) is laid 3–6 weeks after mating. Incubation takes between 5 and 12 weeks. The young measure {{cvt|20|cm|in}} long as hatchlings. Unusually for snakes, their mother may remain with the newly hatched juveniles for a few days. Males and females reach sexual maturity at approximately 5 years of age, when they reach a length of {{cvt|50|cm|in}} and {{cvt|65|cm|in}}, respectively.<ref name = "Wildlist"/>

==Conservation status==
The [[IUCN]] has rated this species as Least Concern. This is a generally abundant species which is tolerant of a wide range of habitats and has a large geographic range.<ref name="iucn status 15 November 2021" />

==Gallery==
<gallery widths="200" heights="140">
Image:ElapheScalaris-Young-199206-France.jpg|Young ''Zamenis scalaris'' in France
Image:Elaphe scalaris in office.jpg|
Image:ElapheScalaris-20030427-Spain.jpg|
Image:Snake (Elaphe scalaris) by JM Rosier.JPG|
Image:Benny Trapp Rhinechis scalaris Jugendzeichnung Portugal.jpg|
</gallery>

==References==
{{Reflist|
refs=
<ref name="Wildlist">[http://www.wildsideholidays.com/natural/reptiles-and-amphibians/314-ladder-snake-elaphe-rhinechis-scalaris-culebra-de-escalera-.html Ladder Snake (''Elaphe'' &#91;''Rhinechis''&#93;] ''scalaris''), ''Culebra de escalera''. {{webarchive|url=https://web.archive.org/web/20120516143647/http://www.wildsideholidays.com/natural/reptiles-and-amphibians/314-ladder-snake-elaphe-rhinechis-scalaris-culebra-de-escalera-.html|date=2012-05-16}} Wildsideholidays.com. Retrieved on 2013-08-15.</ref>
}}

==External links==
*{{usurped|1=[https://web.archive.org/web/20090226135007/http://www.ratsnakefoundation.org/modules/smartsection/item.php?itemid=96 ''Rhinechis scalaris'' Information Sheet]}}

==Further reading==
*[[:fr:Edwin Nicholas Arnold|Arnold EN]], [[species:John A. Burton|Burton JA]] (1978). ''A Field Guide to the Reptiles and Amphibians of Britain and Europe''. London: Collins. 272 pp. + Plates 1–40. {{ISBN|0-00-219318-3}}. (''Elaphe scalaris'', pp.&nbsp;200–201 + Plate 36 + Map 113).
*[[George Albert Boulenger|Boulenger GA]] (1894). ''Catalogue of the Snakes in the British Museum (Natural History). Volume II., Containing the Conclusion of the Colubridæ Aglyphæ.'' London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). xxi + 382 pp. + Plates I-XX. (''Coluber scalaris'', pp.&nbsp;65–66).
*[[Heinrich Rudolf Schinz|Schinz HR]] (1822). ''Das Thierreich eingetheilt nach dem Bau der Thiere als Grundlage ihrer Naturgeschichte und der vergleichenden Anatomie von dem Herrn Ritter von Cuvier. Zweiter Band'' [Volume 2]. ''Reptilien, Fische, Weichthiere, Ringelwürmer.'' Stuttgart and Tübingen: J.G. Cotta. xvi + 835 pp. (''Coluber scalaris'', new species, p.&nbsp;123). (in German).


{{Taxonbar|from=Q1860532}}

[[Category:Zamenis]]
[[Category:Reptiles described in 1822]]
[[Category:Taxa named by Heinrich Rudolf Schinz]]
[[Category:Taxonomy articles created by Polbot]]