Editing Painted turtle (section)

===Subspecies===

Although the subspecies of painted turtle [[Intergradation|intergrade]] (blend together)<!-- intentional construction to share the word, but explain it in article, to convey info while still being accessible, see WP: Technical Articles. --> at range boundaries<ref name="AL intergrade">{{cite web|last=Lee-Sasser|first=Marisa|title=Painted turtle in Alabama|url=http://www.outdooralabama.com/watchable-wildlife/what/Reptiles/Turtles/pt.cfm|publisher=Alabama Department of Conservation and Natural Resources|access-date=2010-08-12|date=December 2007|quote=Intergrades exhibit a mix of characteristics where their ranges overlap.|url-status=dead|archive-url=https://web.archive.org/web/20100830161113/http://www.outdooralabama.com/watchable-wildlife/what/Reptiles/Turtles/pt.cfm|archive-date=2010-08-30}}</ref> they are distinct within the hearts of their ranges.<ref name="Senneke2003">{{cite web |last=Senneke |first=Darrell |date=2003 |title=Differentiating painted turtles (''Chrysemys picta'' ssp) |url=http://www.chelonia.org/Articles/diffpaintedturtles.htm |archive-url=https://web.archive.org/web/20021114140835/http://www.chelonia.org/Articles/diffpaintedturtles.htm |url-status=usurped |archive-date=November 14, 2002 |access-date=2010-12-09 |publisher=World Chelonian Trust}}</ref>

*The male '''eastern painted turtle''' (''C.&nbsp;p.&nbsp;picta'') is {{convert|13|-|17|cm|in|abbr=on|0}} long, while the female is {{convert|14|-|17|cm|in|abbr=on|0}}. The upper shell is olive green to black and may possess a pale stripe down the middle and red markings on the periphery. The segments ([[scute]]s)<!-- the construction here is intentional, to show the word once in parentheses, as it may be seen be readers on other turtle articles, but NOT to repeat it as the drumbeat of technicality vocabularity becomes too strong --> of the top shell have pale leading edges and occur in straight rows across the back, unlike all other North American turtles, including the other three subspecies of painted turtle, which have alternating segments.<ref name="Senneke2003" /> The bottom shell is plain yellow or lightly spotted. Sometimes as few as one dark grey spot near the lower center of the shell.<ref name="Nova Scotia Museum">{{cite web | url = http://museum.gov.ns.ca/amphibians/en/turtles/painted.asp | title = Eastern painted turtle ''Chrysemys picta picta'' (Schneider) | access-date = 2010-09-29 | date = 2007 | publisher = Nova Scotia Museum | url-status = dead | archive-url = https://web.archive.org/web/20101229091522/http://museum.gov.ns.ca/amphibians/en/turtles/painted.asp | archive-date = 2010-12-29 }}</ref>
*The '''midland painted turtle''' (''C.&nbsp;p.&nbsp;marginata'') is {{convert|10|-|25|cm|in|abbr=on|0}} long.<ref name="Natural Resources Canada">{{cite web|url=http://cfs.nrcan.gc.ca/subsite/glfc-amphibians/chrysemys-picta-marginata |title=Midland painted turtle (''Chrysemys picta marginata'') |access-date=2010-09-29 |date=2007-09-24 |publisher=Natural Resources Canada |url-status=dead |archive-url=https://web.archive.org/web/20090421150700/http://cfs.nrcan.gc.ca/subsite/glfc-amphibians/chrysemys-picta-marginata |archive-date=April 21, 2009 }}</ref> The centrally located midland is the hardest to distinguish from the other three subspecies.<ref name="Senneke2003" /> Its bottom shell has a characteristic symmetrical dark shadow in the center which varies in size and prominence.{{sfn|Ernst|Lovich|2009|p=187}}
*The largest subspecies is the '''western painted turtle''' (''C.&nbsp;p.&nbsp;bellii''), which grows up to {{convert|26.6|cm|in|abbr=on|0}} long.{{sfn|Carr|1952|p=221}}<ref>[http://www.cbc.ca/news/canada/saskatchewan/record-setting-painted-western-turtle-found-in-regina-1.3102274 Record-setting Painted Western Turtle found in Regina], CBC News</ref> Its top shell has a mesh-like pattern of light lines,{{sfn|Ernst|Lovich|2009|p=185}} and the top stripe present in other subspecies is missing or faint. Its bottom shell has a large colored splotch that spreads to the edges (further than the midland) and often has red hues.{{sfn|Ernst|Lovich|2009|p=185}}

{| class="wikitable plainrowheaders" style="margin: 1em auto; text-align: center;"
|-
! scope="col" | Eastern painted turtle<br />''C.&nbsp;p.&nbsp;picta''
! scope="col" | Midland painted turtle<br />''C.&nbsp;p.&nbsp;marginata''
! scope="col" | Western painted turtle<br />''C.&nbsp;p.&nbsp;bellii''
|-
| style="border: 0;" | [[File:Painted-Turtle-1 Young.jpg|200px|border|Full overhead shot of an eastern painted turtle]]
| style="border: 0;" | [[File:Chrysemys picta marginata (27730831161) (mirrored).jpg|200px|border|Midland painted turtle standing on tarmac, with neck extended]]
| style="border: 0;" | [[File:A4 Western painted turtle.jpg|200px|border|Western painted turtle standing in grass, with neck extended]]
|-
| style="border: 0;" | [[File:B1 Eastern painted turtle underside.jpg|200px|border|Handled turtle, exposing the orange-yellow undershell (plastron)]]
| style="border: 0;" | [[File:B2 Midland painted turtle underside.jpg|200px|border|alt=An overturned turtle on rocks: the under shell is faint tan with faint black shaded patterns on it.|Under shell (plastron) of a midland painted turtle]]
| style="border: 0;" | [[File:B4 Western painted turtle underside.jpg|200px|border|alt=An overturned turtle on grass: coloring is bright red with black and white Rorshach-like patterns.|Under shell (plastron) of a western painted turtle]]
|}

Until the 1930s, many of the subspecies of the painted turtle were labeled by biologists as full species within ''Chrysemys'', but this varied by the researcher. The painted turtles in the border region between the western and midland subspecies were sometimes considered a full species, ''treleasei''. In 1931, [[Sherman C. Bishop|Bishop]] and [[Franklin J. W. Schmidt|Schmidt]] defined the current "four in one" taxonomy of species and subspecies. Based on comparative measurements of turtles from throughout the range, they subordinated species to subspecies and eliminated ''treleasei''.<ref name="Bishop">{{cite journal | last1 = Bishop | first1 = Sherman | last2 = Schmidt | first2 = F. J. W. | title = The painted turtles of the genus ''Chrysemys'' | pages = 123–139 | journal = Zoological Series | volume = 18 | issue = 4 | date = 1931 | publisher = Field Museum of Natural History | url = https://books.google.com/books?id=9sNJAAAAYAAJ&pg=RA123| access-date = 2011-01-06}}</ref>

Since at least 1958,<ref name="Bleakney 1958">{{cite journal | title = Postglacial dispersal of the turtle ''Chrysemys picta'' | journal = Herpetologica | date = 1958-07-23 | first = Sherman | last = Bleakney | volume = 14 | issue = 2 | pages = 101–104| jstor = 3889448}} {{subscription required}}</ref>{{#tag:ref|Bishop and Schmidt alluded to glacial origins even earlier.<ref name="Bishop" />|group="nb"}} the subspecies were thought to have evolved in response to [[Allopatric speciation|geographic isolation]] during the last ice age, 100,000 to 11,000&nbsp;years ago.{{sfn|Ernst|Lovich|2009|p=185}} At that time painted turtles were divided into three different populations: eastern painted turtles along the southeastern Atlantic coast; southern painted turtles around the southern Mississippi River; and western painted turtles in the southwestern United States.{{sfn|Ernst|Lovich|2009|p=187}} The populations were not completely isolated for sufficiently long, hence wholly different species never evolved. When the glaciers retreated, about 11,000&nbsp;years ago, all three subspecies moved north. The western and southern subspecies met in Missouri and [[Hybrid (biology)|hybridized]] to produce the midland painted turtle, which then moved east and north through the Ohio and Tennessee river basins.<ref name="Bleakney 1958" />{{sfn|Ernst|Lovich|2009|p=187}}

Biologists have long debated the genera of closely related subfamily-mates ''Chrysemys,'' ''[[Pseudemys]]'' (cooters), and ''[[Trachemys]]'' (sliders). After 1952, some combined ''Pseudemys'' and ''Chrysemys'' because of similar appearance.{{sfn|Carr|1952|p=213}} In 1964, based on measurements of the skull and feet, [[Samuel Booker McDowell Jr.|Samuel B. McDowell]] proposed all three genera be merged into one. However, further measurements, in 1967, contradicted this [[Taxonomy (biology)|taxonomic]] arrangement. Also in 1967, [[J. Alan Holman]],<ref>{{cite journal | title = Comments on turtles of the genus ''Chrysemys'' Gray | journal = Herpetologica | date = September 1977 | first = J. Alan | last = Holman | volume = 33 | issue = 3 | pages = 274–276 | jstor = 3891939}} {{subscription required}}</ref> a paleontologist and herpetologist, pointed out that, although the three turtles were often found together in nature and had similar mating patterns, they did not [[crossbreed]]. In the 1980s, studies of turtles' cell structures, biochemistries, and parasites further indicated that ''Chrysemys'', ''Pseudemys'', and ''Trachemys'' should remain in separate genera.{{sfn|Ernst|Barbour|1989|p=203}}

In 2003, Starkey ''et al.'' proposed that ''[[Chrysemys dorsalis]]'', formerly considered a subspecies of ''C.&nbsp;picta'', to be a distinct species sister to all subspecies in ''C.&nbsp;picta''. Although this proposal was largely unrecognized at the time due to evidence of hybridization between ''dorsalis'' and ''picta'', the [[Turtle Taxonomy Working Group]] and the [[Reptile Database]] have since followed through with it, although both the subspecific and specific names have been recognized.{{sfn|Fritz|Havaš|2007|p=177}}<ref>{{Cite web |title=Chrysemys dorsalis |url=https://reptile-database.reptarium.cz/species.php?genus=Chrysemys&species=dorsalis |access-date=2022-03-28 |website=The Reptile Database}}</ref><ref name="Rhodin"/>