Deirochelys
{{Short description|Genus of turtles}}
{{Automatic taxobox
| fossil_range = Miocene - Recent
| image = Deirochelys reticularia 2008-11-02 289.jpg
| image_caption = Chicken turtle (D.{{nbsp}}reticularia) basking
| taxon = Deirochelys
| authority = Agassiz, 1857
| type_species = Deirochelys reticularia
| type_species_authority = Latreille, 1801
| subdivision_ranks = Species
| subdivision_ref = {{cite web |title=Deirochelys |url=https://www.mindat.org/taxon-2443153.html |website=Mindat.org|access-date=2022-05-12}}
| subdivision =
| synonyms =
}}
Deirochelys is a genus of freshwater turtle in the family Emydidae, the pond and marsh turtles. It contains one extant species, the chicken turtle (Deirochelys reticularia), which is native to the southeastern United States. A second extinct member, Deirochelys carri, is known from a fossil found in Alachua County, Florida.{{cite journal| last=Jackson
|first=Dale R. |journal=Tulane Studies in Zoology and Botany |title=Evolution and fossil record of the chicken turtle Deirochelys, with a re-evaluation of the genus |year=1978 |volume=20 |page=43 |publisher=Tulane University |location=New Orleans, Louisiana |url=https://www.biodiversitylibrary.org/page/4270378 |access-date=2022-05-15}} The genus was first described by Louis Agassiz in 1857,{{cite book |last=Agassiz |first=Louis |author-link=Louis Agassiz |title=Contributions to the natural history of the United States of America |volume=1 |year=1857 |publisher=Little, Brown and Company |location=Boston, Massachusetts |doi=10.5962/bhl.title.12644 |url=https://www.biodiversitylibrary.org/item/46159#page/501/mode/1up |access-date=2022-05-15}} and its name is derived from the Ancient Greek words for "neck" (deirḗ) and "tortoise" (khélūs), referring to the particularly long necks of these turtles.{{cite web|url=https://services.dwr.virginia.gov/fwis/booklet.html?Menu=_.Taxonomy&bova=030064&version=19106|title=Taxonomy chapter for Turtle, eastern chicken (030064)|work=BOVA booklet|publisher=Virginia Fish and Wildlife Information Service|access-date=2022-04-24}}
Evolution
Like other emydids (members of the family Emydidae), Deirochelys{{`}} karyotype consists of 2N=50 chromosomes.{{cite journal |last=Killebrew |first=Flavius C. |title=Mitotic chromosomes of turtles. IV. The Emydidae |journal=Texas Journal of Science |volume=29 |issue=3/4 |pages=245–254 |year=1977 |publisher=Texas Academy of Science |url=https://www.biodiversitylibrary.org/item/249779 |accessdate=2022-04-25}} A 1996 study of various turtles' mitochondrial DNA supported the partition of Emydidae into two subfamilies, Emydinae and Deirochelyinae, with Deirochelys placed within the latter. Deirochelys was reported to be the sister genus to the rest of the subfamily, meaning it shares a common ancestor with the ancestor of all the other genera in Deirochelyinae.{{cite journal |last1=Bickham |first1=John W. |last2=Lamb |first2=Trip |last3=Minx |first3=Patrick |last4=Patton |first4=John C. |title=Molecular systematics of the genus Clemmys and the intergeneric relationships of emydid turtles |journal=Herpetologica |volume=52 |issue=1 |pages=89–97 |year=1996 |jstor=3892960 }} Alternative analysis by Stephens and Wiens found that under certain analyses Deirochelys could instead be described as a sister taxon to Emydinae or indeed to the family Emydidae itself. The authors attributed this confusion to long-branch attraction and concluded that Deirochelys did indeed sit within Deirochelyinae.{{cite journal |last1=Stephens |first1=Patrick R. |last2=Wiens |first2=John J. |title=Ecological diversification and phylogeny of emydid turtles |journal=Biological Journal of the Linnean Society |volume=79 |pages=577–610 |year=2003 |issue=4 |doi=10.1046/j.1095-8312.2003.00211.x |doi-access=free }} Spinks et al. (2009) also found Deirochelys to be a sister to Emydidae under maximum parsimony.{{cite journal |last1=Spinks |first1=Phillip Q. |last2=Thomson |first2=Robert C. |last3=Lovely |first3=Geoff A. |last4=Shaffer |first4=H. Bradley |title=Assessing what is needed to resolve a molecular phylogeny: simulations and empirical data from emydid turtles |journal=BMC Evolutionary Biology |volume=9 |page=56 |year=2009 |issue=1 |doi=10.1186/1471-2148-9-56 |pmid=19284630 |pmc=2660309 |url=https://bmcecolevol.biomedcentral.com/track/pdf/10.1186/1471-2148-9-56.pdf |doi-access=free |bibcode=2009BMCEE...9...56S }}
It has been proposed that Deirochelys and the painted turtles Chrysemys are among the most ancient emydids, having diverged from the rest of the emydids more than 24.4 million years ago. The genus Deirochelys itself is thought to have evolved before the end of the Clarendonian, over 10.3 million years ago.{{cite journal |last=Jasinski |first=Stephen E. |title=A new slider turtle (Testudines: Emydidae: Deirochelyinae: Trachemys) from the late Hemphillian (late Miocene/early Pliocene) of eastern Tennessee and the evolution of the deirochelyines |journal=PeerJ |volume=6 |year=2018 |pages=e4338 |doi=10.7717/peerj.4338 |pmid=29456887 |pmc=5815335 |doi-access=free }}
{{cladogram
|title=Bickham, et al. 1996
|cladogram={{clade
|label1=Emydidae
|1={{clade
|1=Emydinae
|2={{clade
|label1=Deirochelyinae
|1={{clade
|1=Deirochelys
|2={{clade
|1=Chrysemys
|2=Pseudemys
|3={{clade
|1=Malaclemys
|2={{clade|1=Graptemys|2=Trachemys}}
}}
}}
}}
}}
}}
}}
| align = center
}}
{{cladogram
|title=Spinks, et al. 2009
|cladogram={{clade
|label1=Testudinoidea
|1={{clade
|1=Deirochelys
|2={{clade
|2=Emydinae
}}
|label2=Emydidae
}}
}}
| align = center
}}
Species
There are two currently accepted species:
- Deirochelys reticularia (chicken turtle)
- Deirochelys carri
A possible third species, D.{{nbsp}}floridana, was described by Oliver Perry Hay in 1908 from a fossil specimen. In 1964, C.G. Jackson determined the specimen to instead be D.{{nbsp}}reticularia, but in 1974 he reassigned it to the genus Chrysemys. Jasinski (2018) reasserted that this turtle did indeed represent a separate species of Deirochelys.
References
{{reflist}}
{{Emydidae}}
{{Taxonbar|from=Q14566118}}
Category:Reptile genera with one living species