The Kinosternidae are a

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

of mostly small

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 ...

s that includes the

mud turtle ''Kinosternon'' is a genus of small aquatic turtles from the Americas known commonly as mud turtles. Geographic range They are found in the United States, Mexico, Central America, and South America. The greatest species richness is in Mexico, ...

s and musk turtles. The family contains 25

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), ...

within four

genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

, but taxonomic reclassification is an ongoing process, so many sources vary on the exact numbers of species and

subspecies In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (Morphology (biology), morpholog ...

. They inhabit slow-moving bodies of water, often with soft, muddy bottoms and abundant vegetation.

Description

Most kinosternids are small turtles, in carapace length. The highly

dome A dome () is an architectural element similar to the hollow upper half of a sphere. There is significant overlap with the term cupola, which may also refer to a dome or a structure on top of a dome. The precise definition of a dome has been a m ...

d carapace has a distinct keel down its center. The genus '' Staurotypus'' gets much larger, to . Females are generally larger than males, but males have much longer

tail The tail is the elongated section at the rear end of a bilaterian animal's body; in general, the term refers to a distinct, flexible appendage extending backwards from the midline of the torso. In vertebrate animals that evolution, evolved to los ...

s. Kinosternids can be

black Black is a color that results from the absence or complete absorption of visible light. It is an achromatic color, without chroma, like white and grey. It is often used symbolically or figuratively to represent darkness.Eva Heller, ''P ...

brown Brown is a color. It can be considered a composite color, but it is mainly a darker shade of orange. In the CMYK color model used in printing and painting, brown is usually made by combining the colors Orange (colour), orange and black. In the ...

green Green is the color between cyan and yellow on the visible spectrum. It is evoked by light which has a dominant wavelength of roughly 495570 nm. In subtractive color systems, used in painting and color printing, it is created by a com ...

, or

yellow Yellow is the color between green and orange on the spectrum of light. It is evoked by light with a dominant wavelength of roughly 575585 nm. It is a primary color in subtractive color systems, used in painting or color printing. In t ...

ish in color. Most species do not have shell markings, but some species have radiating black markings on each

carapace A carapace is a dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the unde ...

scute A scute () or scutum (Latin: ''scutum''; plural: ''scuta'' "Scutum (shield), shield") is a bony external plate or scale overlaid with horn, as on the shell of a turtle, the skin of crocodilians, and the feet of Bird anatomy#Scales, birds. The ter ...

. Some species have distinctive yellow striping along the sides of the head and neck. The musk turtles are so named because they are capable of releasing a foul-smelling musk from glands under the rear of their shells when disturbed. They are native to North America and South America.

Diet

All members of the family are

carnivorous A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose nutrition and energy requirements are met by consumption of animal tissues (mainly mu ...

, feeding on

crustacean Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthrop ...

s, aquatic

insect Insects (from Latin ') are Hexapoda, hexapod invertebrates of the class (biology), class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (Insect morphology#Head, head, ...

mollusk Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...

annelid The annelids (), also known as the segmented worms, are animals that comprise the phylum Annelida (; ). The phylum contains over 22,000 extant species, including ragworms, earthworms, and leeches. The species exist in and have adapted to vario ...

amphibian Amphibians are ectothermic, anamniote, anamniotic, tetrapod, four-limbed vertebrate animals that constitute the class (biology), class Amphibia. In its broadest sense, it is a paraphyletic group encompassing all Tetrapod, tetrapods, but excl ...

s, small

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

, and sometimes

carrion Carrion (), also known as a carcass, is the decaying flesh of dead animals. Overview Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters (or scavengers) include crows, vultures ...

. They also eat vegetation such as aquatic plants. In captivity they can eat red and green leaf lettuce.

Reproduction

Kinosternids lay about four hard-shelled eggs during the late spring and early summer. After hatching, some species overwinter in a subterranean nest, emerging the following spring. Some adults also spend the winter on land, constructing a burrow with a small air hole used on warm days. Kinosternids contain the only

known, or at least suspected, to exhibit parental care. Studies of the yellow mud turtle in

Nebraska Nebraska ( ) is a landlocked U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders South Dakota to the north; Iowa to the east and Missouri to the southeast, both across the Missouri River; Ka ...

, United States, suggest females sometimes stay with the nest and may urinate on the eggs long after laying, to either keep them moist or to protect them from

snake Snakes are elongated limbless reptiles of the suborder Serpentes (). Cladistically squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales much like other members of the group. Many species of snakes have s ...

predation (by making them less palatable). Some kinosternids, particularly those in the genera ''

Claudius Tiberius Claudius Caesar Augustus Germanicus ( ; ; 1 August 10 BC – 13 October AD 54), or Claudius, was a Roman emperor, ruling from AD 41 to 54. A member of the Julio-Claudian dynasty, Claudius was born to Nero Claudius Drusus, Drusus and Ant ...

'' and '' Staurotypus'', exhibit genetic sex determination; in ''Staurotypus'' this is XY sex determination, and the same is suspected to be true of ''Claudius'' as well. ''

Kinosternon ''Kinosternon'' is a genus of small aquatic turtles from the Americas known commonly as mud turtles. Geographic range They are found in the United States, Mexico, Central America, and South America. The greatest species richness is in Mexico, a ...

'' and '' Sternotherus'' have

temperature-dependent sex determination Temperature-dependent sex determination (TSD) is a type of environmental sex determination in which the temperatures experienced during embryonic/larval development determine the sex of the offspring. It is observed in reptiles and teleost fish, ...

as is typical of turtles.

Taxonomy

Family Kinosternidae * Genus †'' Baltemys velogastros'' * Genus †'' Xenochelys floridensis'' * Genus †'' Yelmochelys'' * Subfamily Kinosterninae ** Genus ''

'' ***

Tabasco mud turtle The Tabasco mud turtle (''Kinosternon acutum''), commonly known as pochitoque in Tabasco, Mexico, is a small turtle which belongs to the family Kinosternidae. It can be found in central Veracruz, Tabasco, northern Guatemala and Belize. This turt ...

- ''K. acutum''

Gray Grey (more frequent in British English) or gray (more frequent in American English) is an intermediate color between black and white. It is a neutral or achromatic color, meaning that it has no chroma. It is the color of a cloud-covered s ...

, 1831 *** Alamos mud turtle - ''K. alamosae''

Berry A berry is a small, pulpy, and often edible fruit. Typically, berries are juicy, rounded, brightly colored, sweet, sour or tart, and do not have a stone or pit although many pips or seeds may be present. Common examples of berries in the cul ...

& Legler, 1980 *** Central American mud turtle - ''K. angustipons'' Legler, 1965 ***

Arizona mud turtle The Arizona mud turtle (''Kinosternon stejnegeri'') is a species of mud turtle in the family Kinosternidae found in the deserts of Arizona (United States) and Sonora (Mexico). It is a semi-aquatic turtle. It lives in impermanent puddles, and ...

- ''K. arizonense'' Gilmore, 1923 *** Striped mud turtle - ''K. baurii'' ( Garman, 1891) ***

Jalisco mud turtle The Jalisco mud turtle (''Kinosternon chimalhuaca'') is a species of mud turtle in the Kinosternidae family endemic to Mexico. It is found in Colima and Jalisco. They live in freshwater habitats like swamps or quiet rivers. Jalisco mud turtles ...

- ''K. chimalhuaca'' Berry, Seidel, & Iverson, 1996 ***

Creaser's mud turtle Creaser's mud turtle (''Kinosternon creaseri'') is a species of mud turtle in the Family (biology), family Kinosternidae. The species is Endemism, endemic to the Yucatán Peninsula in southeastern Mexico. The Specific name (zoology), specific na ...

- ''K. creaseri'' Hartweg, 1934 *** Dunn's mud turtle - ''K. dunni'' Schmidt, 1947 *** Durango mud turtle - ''K. durangoense'' Iverson, 1979 *** Yellow mud turtle - ''K. flavescens'' (

Agassiz Jean Louis Rodolphe Agassiz ( ; ) FRS (For) FRSE (May 28, 1807 – December 14, 1873) was a Swiss-born American biologist and geologist who is recognized as a scholar of Earth's natural history. Spending his early life in Switzerland, he recei ...

, 1857) *** Herrera's mud turtle - ''K. herrerai'' Stejneger, 1925 *** Rough-footed mud turtle - ''K. hirtipes'' ( Wagler, 1830) ****Valley of Mexico mud turtle - ''K. h. hirtipes'' (Wagler, 1830) ****Lake Chapala mud turtle - ''K. h. chapalaense'' (Iverson, 1981) ****San Juanico mud turtle - ''K. h. magdalense'' (Iverson, 1981) ****Viesca mud turtle - ''K. h. megacephalum'' (extinct) (Iverson, 1981) ****Mexican plateau mud turtle - ''K. h. murrayi'' (Glass and Hartweg, 1951) ****Patzcuarco mud turtle - ''K. h. tarascense'' (Inverson, 1981) *** Mexican mud turtle - ''K. integrum'' (LeConte, 1954) *** White-lipped mud turtle - ''K. leucostomum'' Duméril, Bibron & Duméril, 1851 ****Northern white-lipped mud turtle - ''K. l. leucostomum'' Duméril, Bibron & Duméril, 1851 ****Southern white-lipped mud turtle - ''K. l. postinguinale'' (Cope, 1887) *** Oaxaca mud turtle - ''K. oaxacae'' Berry & Iverson, 1980 ***

Scorpion mud turtle The scorpion mud turtle or Tabasco mud turtle (''Kinosternon scorpioides'') is a species of mud turtle in the family Kinosternidae. It is found in Mexico, Central and South America. Description The scorpion mud turtle is a medium to large kin ...

- ''K. scorpioides'' (

Linnaeus Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...

, 1766) ****Scorpion mud turtle (subspecies) - ''K. s. scorpioides'' (Linnaeus, 1766) ****Central Chiapas mud turtle - ''K. s. abaxillare'' (Baur, 1925) ****White-throated mud turtle - ''K. s. albogulare'' (Duméril and Bibron, 1870) ****Red-cheeked mud turtle - ''K. s. cruentatum'' (Duméril, Bibron & Duméril, 1851) *** Sonora mud turtle - ''K. sonoriense'' ( Le Conte, 1854) ****Sonora mud turtle (subspecies) - ''K. s. sonoriense'' (Le Conte, 1854) ****Sonoyta mud turtle - ''K. s. longifemorale'' (Inverson, 1981) *** Eastern mud turtle - ''K. subrubrum'' ( Bonnaterre, 1789) ****Eastern mud turtle (subspecies) - ''K. s. subrubrum'' (Bonnaterre, 1789) ****Mississippi mud turtle - ''K. s. hippocrepis'' (Bonnaterre, 1789) ****Florida mud turtle - ''K. s. steindachneri'' (Siebenrock, 1906) ** Genus '' Sternotherus'' *** Razor-backed musk turtle, ''S. carinatus'' (Gray, 1856) *** Flattened musk turtle, ''S. depressus'' ( Tinkle & Webb, 1955) *** Intermediate musk turtle, ''S. intermedius'' Scott, Glenn & Rissler, 2017 *** Loggerhead musk turtle, ''S. minor'' (

, 1857) *** Common musk turtle or stinkpot, ''S. odoratus'' (Sonnini & Latreille, 1801) *** Stripeneck musk turtle, ''S. peltifer'' (Smith & Glass, 1947) * Subfamily Staurotypinae ** Genus ''

'' *** Narrow-bridged musk turtle, ''C. angustatus'' Cope, 1865 ** Genus '' Staurotypus'' *** Giant musk turtle, ''S. salvinii'' Gray, 1864 *** Mexican musk turtle, ''S. triporcatus'' ( Wiegmann, 1828)

Additional images

References

Animal Diversity Web: Family Kinosternidae, by Keith Pecor
;Bibliography * {{Authority control Reptiles of North America Taxa named by Louis Agassiz Turtle families