Cryptoblepharus egeriae: Difference between revisions

{{short description|Species of reptile}}{{Use dmy dates|date=July 2019}}

{{for|other species sometimes known as blue-tailed skink|Blue-tailed skink (disambiguation)}}{{Speciesbox

| status_ref =<ref name="iucn status 18 November 2021">{{cite iucn |author=Woinarski, J.C.Z. |author-link=species:John C.Z. Woinarski |author2=Cogger, H. |author2-link=Harold Cogger |author3=Mitchell, N.M. |author4=Emery, J. |author4-link=species:Jon-Paul Emery |date=2017 |title=''Cryptoblepharus egeriae'' |volume=2017 |page=e.T102327291A102327566 |doi=10.2305/IUCN.UK.2017-3.RLTS.T102327291A102327566.en |access-date=18 November 2021}}</ref>

| synonyms_ref =<ref>"''{{EMBL species|genus=Cryptoblepharus |species=egeriae'' ". The Reptile Database.}} www.reptile-database.org.</ref>

The '''''Cryptoblepharus egeriae''''', more commonlyalso known [[Common name|commonly]] as the '''blue-tailed shinning-skink''', the '''Christmas Island Blueblue-Tailedtailed Skinkshinning-skink''', and the '''Christmas Island blue-tailed skink''', is a [[species]] of [[lizard]] in the [[Family (biology)|family]] [[Scincidae]] that was once inhabitedendemic to [[Christmas Island]]. The Christmas Island Blueblue-Tailedtailed Skinkskink was discovered in 18861888.<ref name=":1">{{Cite journal |lastauthor=Boulenger GA|firstauthor-link=G.George A.Albert Boulenger |date=2009-08-201888 |title=On the Reptiles of Christmas Island |url=https://zslpublications.onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.1888.tb06729.x |journal=Proceedings of the Zoological Society of London |volume=561888 |issue=1 |pages=534–536 |doi=10.1111/j.1469-7998.1888.tb06729.x |issn=0370-2774}} (''Ablepharus egeriae'', new species, pp. 535–536).</ref> InIt 2002was scientistsformerly withthe most abundant reptile on the island, and occurred in high numbers particularly near the human settlement. However, the Christmas Island Nationalblue-tailed Parksskink discoveredbegan thatto decline sharply outwardly from the human settlement by the early 1990s, which coincided with the introduction of a predatory snake and also followed the introduction of the yellow crazy ant (''[[yellow crazy ant|Anoplolepis gracilipes]]'') was becoming a threat toin the Christmas Island Bluemid-Tailed Skink1980s.<ref name=":0">{{Cite webjournal |titlelast=Yellow crazy ant biocontrolEmery |urlfirst=https://parksaustralia.gov.au/christmas/discover/nature/conservation/yellowJon-crazy-ant-biocontrol/Paul |access-date=2022-03-242021 |websitetitle=parksaustralia.gov.auThe |language=en-au}}</ref>lost Sincelizards theirof introductionChristmas inIsland: 1980A retrospective assessment of factors driving the yellowcollapse crazyof antsa hadnative startedreptile tocommunity massively|url=https://conbio.onlinelibrary.wiley.com/doi/10.1111/csp2.358 disrupt|journal=Conservation theScience [[biodiversity]]and onPractice Christmas|volume=3 Island|issue=2|doi=10.<ref1111/csp2.358 name|s2cid="234078176 |hdl=10536/DRO/DU:0"30147604 |hdl-access=free }}</ref> ThisBy discovery put2006, the Christmas Island Blueblue-Tailedtailed Skinkskink was on the endangered animals list in 2006.,<ref name=":2">{{Cite web |title=Options beyond captivity for two critically endangered Christmas Island reptiles |url=https://www.nespthreatenedspecies.edu.au/projects/options-beyond-captivity-for-two-critically-endangered-christmas-island-reptiles#:~:text=The%20blue-tailed%20skink%20(Cryptoblepharus,rapidly%20from%20the%20late%201980s. |access-date=2022-03-24 |website=www.nespthreatenedspecies.edu.au}}</ref> Byand 2009by 2010 the Christmas Island blue-tailed skink was [[Tarongaextinct Zooin the wild]]. decidedFrom 2009 to start2010, anParks activeAustralia breedingand program[[Taronga inZoo]] hopesstarted ofa beingcaptive ablebreeding toprogram, releasewhich somehas ofprevented thetotal skinksextinction back intoof the wildspecies.<ref name=":3">{{Cite web |title=Saving the Blue-Tailed Skink |url=http://www.taronga.org.au/media-release/2019-09-12/saving-blue-tailed-skink |access-date=2022-03-24 |website=Saving the Blue-Tailed Skink {{!}} Taronga Conservation Society Australia |language=en}}</ref> However, by 2010 the Christmas Island Blue-Tailed Skink was [[extinct in the wild]].

The [[Specific name (zoology)|specific name]], ''egeriae'', is in honor of [[HMS Egeria (1873)|HMS ''Egeria'']].<ref name=":4">[[species:Bo Beolens|Beolens, Bo]]; [[species:Michael Watkins|Watkins, Michael]]; Grayson, Michael (2011). ''The Eponym Dictionary of Reptiles''. Baltimore: Johns Hopkins University Press. xiii + 296 pp. {{ISBN|978-1-4214-0135-5}}. (''Cryptoblepharus egeriae'', p. 81).</ref>

The Christmas islandIsland blue-tailed skink typically grows to bea 4[[Snout–vent length|snout-5cm into-vent length]] (SVL) of {{cvt|4|–|5|cm|in}}.<ref name=":2" /> It can be identified by its small black body with two yellow stripsstripes running vertically down the skink's back and intoonto its vibrant blue tail. The skink can use its blue tail to draw a predator’spredator's attention away from its body by separating its tail from its body. The bright colourcolor of the skink's tail means predators are much more likely to notice the tail than the skink's black body.<ref name=":1" />

The Christmas Island blue-tailed skink is a forager known as an [[insectivore]].<ref name=":2" /> TheirIts diet primarily consists of [[Cricket (insect)|crickets]], [[Beetle|beetlesbeetle]]s, [[Fly|flies]], [[Grasshopper|grasshoppersgrasshopper]]s, [[Spider|spidersspider]]s, and [[Earthworm|earthwormsearthworm]]s. TheyIt will occasionally eat some [[vegetation]], though insects remain theirits primary source of food. Because of its small size, the Christmas Island blue-tailed skink forages for its food on the ground, over exposed rocks and low-layinglying vegetation, and will generally only eat prey that are slower moving.<ref name=":4" />

For the Christmas Island blue-tailed skink, theirthe first [[Seasonal breeder|breeding season]] occurs when theymales and females are approximately one year old.<ref name=":4" /> The Christmas Island blue-tailed skink typically lives for seven years in the wild, six of which are active breeding years. The male Christmas Island blue-tailed skink will demonstrate [[Courtship display|courtship]] behaviour when trying to find a mate. The female Christmas Island blue-tailed skink will emit biochemicals for the males to smell, letting them know that the female is in her fertile stage of [[reproduction]].<ref name=":1" /> Male Christmas Island blue-tailed skinks will often fight each other to win a female mate during breeding season. These skinks are [[PolygynyAnimal sexual behaviour#Polygamy|polygamous]] which increases their chance of having offspring. Once the female Christmas Island blue-tailed skink has been fertilized, they arebeing [[oviparous]], andit will generally lay two eggs at a time, with a 75-day [[incubation period]].<ref name=":4" />

TheUntil the late 1990s, the Christmas Island blue-tailed skink iswas [[Endemism|endemic]] to [[Christmas Island]] and could be found all over the island.<ref name=":5" /> UntilIt thecurrently lateexists 1990s,in thecaptive blue-tailedpopulations skinkon couldChristmas beIsland, foundat overTaronga theZoo, wholeand ofon Christmasa Island.small Theisland species'(Pulu distributionBlan) became more sparse oncein the [[yellowCocos crazy(Keeling) antIslands]] waswhere introducedit tohas thebeen island,released leadingas topart aof declinean in[[Assisted themigration|assisted Christmascolonization]] Island blue-tailed skink's populationtrial.<ref name=":13" />

''C. egeriae'' is most closely related to the [[Cryptoblepharus metallicus|''metallicus'']] group of ''[[Cryptoblepharus]],'' native to Australia, with the estimated divergence of ''C. egeriae'' from the group taking place around 7seven million years ago,.<ref name=":5">{{Cite journal |lastlast1=Oliver |firstfirst1=Paul M. |author-link=species:Paul M. Oliver |last2=Blom |first2=Mozes P. K. |last3=Cogger |first3=Harold G. |last4=Fisher |first4=Robert N. |author4-link=species:Robert N. Fisher |last5=Richmond |first5=Jonathan Q. |last6=Woinarski |first6=John C. Z. |date=2018-06-30 |title=Insular biogeographic origins and high phylogenetic distinctiveness for a recently depleted lizard fauna from Christmas Island, Australia |url= |journal=Biology Letters |volume=14 |issue=6 |pages=20170696 |doi=10.1098/rsbl.2017.0696 |pmc=6030605 |pmid=29899126}}</ref> It has an XY sex determination system,<ref name=":6" /> which is likely shared across all major skink lineages.

* [[List of reptiles of Christmas Island]]