The southern painted turtle (''Chrysemys dorsalis'') is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

turtle Turtles are reptiles of the order (biology), order Testudines, characterized by a special turtle shell, shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Crypt ...

in the family Emydidae. It is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the south-central

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

Taxonomy

The southern painted turtle was formerly considered a subspecies of the more widespread

painted turtle The painted turtle (''Chrysemys picta'') is the most widespread native turtle of North America. It lives in relatively slow-moving fresh waters, from southern Canada to northern Mexico, and from the Atlantic to the Pacific. They have been shown ...

(''C. picta'') as ''C. picta dorsalis'', and its exact status is still debated. Since the 1950s, the southern painted turtle, alongside the subspecies of ''C. picta'', was generally thought to have originated following geographic isolation as a result of the

Quaternary glaciation The Quaternary glaciation, also known as the Pleistocene glaciation, is an alternating series of glacial period, glacial and interglacial, interglacial periods during the Quaternary period that began 2.58 Year#SI prefix multipliers, Ma (million ...

, with the populations being isolated for too short a time to fully diverge into distinct species. However, David E. Starkey and collaborators advanced a new view of the subspecies in 2003. Based on a study of the

mitochondrial DNA Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondrion, mitochondria organelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the D ...

, they rejected the glacial development theory and argued that the southern painted turtle should be elevated to a separate species, ''C. dorsalis'', while the other subspecies should be collapsed into one and not differentiated. However, this proposition was largely unrecognized because successful breeding between all subspecies was documented wherever they overlapped. Nevertheless, in 2010, the

IUCN The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...

recognized both ''C. dorsalis'' and ''C. p. dorsalis'' as valid names for the southern painted turtle. In 2014, the

Turtle Taxonomy Working Group The Turtle Taxonomy Working Group (TTWG) is an informal working group of the IUCN/SSC Tortoise and Freshwater Turtle Specialist Group (TFTSG). It is composed of a number of leading turtle taxonomists, with varying participation by individual partici ...

(TTWG) and the

Reptile Database The Reptile Database is a scientific database that collects taxonomic information on all living reptile species (i.e. no fossil species such as dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared ...

reclassified ''C. dorsalis'' as a distinct species, although the TTWG also recognized ''C. p. dorsalis'' as a valid name. The TTWG continued to recognize ''C. dorsalis'' as a distinct species in their 2021 publication.

Description

The smallest member of ''Chrysemys'', it is smaller than any of the subspecies of ''C. picta'' at about long. Its top stripe is a prominent red, and its bottom shell is tan and spotless or nearly so.

Ecology

This species' diet changes with age. Juveniles' diet consists of 13% vegetation, while the adults eat 88% vegetation. This perhaps shows that the turtle prefers small larvae and other prey, but can only obtain significant amounts while young. The reversal of feeding habits with age has also been seen in the false map turtle, which inhabits some of the same range. The most common plants eaten by adult southern painted turtles are

duckweed Lemnoideae is a subfamily of flowering aquatic plants, known as duckweeds, water lentils, or water lenses. They float on or just beneath the surface of still or slow-moving bodies of fresh water and wetlands. Also known as bayroot, they arose fr ...

and algae, and the most common prey items are dragonfly larvae and

crayfish Crayfish are freshwater crustaceans belonging to the infraorder Astacidea, which also contains lobsters. Taxonomically, they are members of the superfamilies Astacoidea and Parastacoidea. They breathe through feather-like gills. Some spe ...

Distribution

The southern painted turtle ranges from extreme southern Illinois and Missouri, roughly along the Mississippi River Valley, to the south. In Arkansas, it branches out to the west towards Texas, where it is found in the far northeast part of that state (

Caddo Lake Caddo Lake () is a lake and bayou (wetland) on the border between Texas and Louisiana, in northern Harrison County and southern Marion County in Texas and western Caddo Parish in Louisiana. The lake is named after the Caddoans or Caddo, ...

region) as well as extreme southeastern Oklahoma ( McCurtain County). It is found in much of Louisiana, where it reaches the Gulf of Mexico (in fresh water). Eastward it is found in western Tennessee, northern Mississippi and much of Alabama, including the Gulf Coast city of Mobile. An isolated population in central Texas has been reported but is now believed to be non-native.

Life history

It has a smaller clutch size than ''C. picta'', at about 4.2 eggs per clutch.

References

Bibliography

* * * * * {{Taxonbar, from=Q2381029 Chrysemys Turtles of North America Endemic reptiles of the United States Reptiles described in 1857 Taxa named by Louis Agassiz