Trachemys dorbigniBlack-bellied Slider

Geographic Range

Black-bellied sliders (Trachemys dorbigni) are native to the Neotropical region. Their distribution includes southern parts of Brazil, ranging south to Uruguay and extending west to northeastern Argentina.

Due to the release of black-bellied sliders in the pet trade, they have become invasive in areas outside of their native habitat, such as northeastern Brazil. Black-bellied sliders are considered a non-native species in Miami, Florida, having been recorded just once in 1964. (Bujes, et al., 2011; Fonseca, et al., 2021; Santana, et al., 2014)

Habitat

Black-bellied sliders are freshwater turtles commonly found off the coast in southeastern South America. They use both urban and suburban areas, and often inhabit tropical wetlands such as ponds, rivers, lakes, and forested areas. Black-bellied sliders live in warm, tropical environments with an average annual temperature of 19 °C. They prefer lowlands like marshes, swamps, and lagoons. They can be found at elevations ranging from 0 to 170 m, but typically are found at 30 to 40 m above sea level.

Female black-bellied sliders often nest in sandy or clay soils around thick vegetation. Nesting sites vary, but a report in 2014 found them nesting up to 250 m from bodies of water. (Alcalde, et al., 2012; Bager, 2010; Bager, 2014; Bager, et al., 2014; Bujes, et al., 2011; Clavijo-Baquet and Magnone, 2017; Fonseca, et al., 2021)

  • Aquatic Biomes
  • lakes and ponds
  • coastal
  • Range elevation
    0 to 170 m
    0.00 to 557.74 ft
  • Average elevation
    30 m
    98.43 ft

Physical Description

Black-bellied sliders exhibit sexual dimorphism, as females tend to be larger than males in all characteristics except tail and foreclaw length. Females range in carapace length (CL) from 143 to 252 mm. Males are slightly smaller, with a CL range of 152 to 200 mm. Females range in carapace width from 117 to 212 mm and males range from 119 to 151 mm. Mass ranges from 0.54 to 2.55 kg in females (average: 1.39 kg) and 0.50 to 1.40 kg (average: 0.87 g) in males.

At black-bellied slider nesting sites, eggs range from 28 to 47 mm in length and 12 to 29 mm wide. Juveniles have an average CL of 102.5 mm and weigh on average 0.22 kg. Juveniles also have circular shells with green carapaces, usually displaying bright orange or yellow marks. In a 2010 report, cases of albinism in juveniles have been reported. Albino hatchlings had an average CL of 31.9 mm, while typical hatchlings had an average CL of 35.9 mm.

The carapaces of adult black-bellied sliders are more oval-shaped with curved sides, consisting of 38 scutes. Their carapaces also have yellow or orange bars that branch or bend to form patterns extending from the center along plastral seams. The base color of their heads, tails, limbs, and carapaces are typically brown or olive green. In later development, females tend to retain more of an olive color, whereas males turn dark brown as they age. A yellow or orange linear stripe extends posteriorly along their jaws and temporal regions of their heads in both sexes. Black-bellied sliders are considered ectothermic, often basking to maintain suitable body temperatures.

Red-eared sliders (Trachemys scripta) may be distinguished from black-bellied sliders by a red stripe extending along their jaws. Other than the color of this stripe, these two species are nearly identical. Red-eared sliders are also native to the southern United States. (Bager, 2010; Bujes, et al., 2011; Cleiton and Giuliano-Caetano, 2008; Kurzmann Fagundes, et al., 2010; Seidel, 1989; Siedel, 2002; Verrastro and Bujes, 2007)

  • Sexual Dimorphism
  • female larger
  • sexes colored or patterned differently
  • female more colorful
  • sexes shaped differently
  • Range mass
    0.50 to 2.55 kg
    1.10 to 5.62 lb
  • Range length
    143 to 252 mm
    5.63 to 9.92 in

Development

During incubation, black-bellied sliders exhibit temperature-dependent sex determination. Nests incubating at lower temperatures have male-biased sex ratios, and females are more common at warmer incubation temperatures. Incubation temperatures range from 26 to 34 °C, but an exact inflection point where the sex ratio switches has not been reported. In captive conditions and constant temperatures, eggs successfully hatched at temperatures ranging from 25 to 31.5 °C.

Black-bellied slider hatchlings develop from a nest with a mean clutch size of 8.2 eggs. Upon hatching, they are 3.5 mm wide and begin growing immediately. Black-bellied sliders exhibit intermediate growth. This means they continue to grow throughout their life, although their growth rate decreases with age and size. Females grow larger than males. With intermediate growth in mind, a maximum CL of 215 mm in males and 255 mm in females has been recorded in previous literature. Females grow much quicker than males, although growth rate decreases with size in both sexes. (Czerwinski, et al., 2016; Fagundes, et al., 2010; Kurzmann Fagundes, et al., 2010; Seidel, 1989; Seidel, 1990)

Reproduction

Black-bellied sliders are polygynandrous, meaning females and males mate with more than one partner throughout their lives. Mating is most frequent in the mornings (700 to 1200 h) from April to July. Sound plays a role in courtship as both juvenile and adult males produce screeches when attracting a mate. Black-bellied sliders use head movements such as vibrating, swinging, or hitting, and they use chemicals secreted from specialized glands under their chins as a sexual-recognition cue. A study in 2015 observed gulping as an act of courtship, where male turtles expel water out of their mouths or noses onto females. Receptivity from females is important when mating, as females will either accept or reject the advances of males. If accepting a potential mate, females also display courtship behavior such as nudging, biting, or rubbing their heads on the dorsal surfaces of their mates. These courtship behaviors eventually lead to copulation.

Most nesting sites are typically flat and located 2 to 4 m above water level and dug around 12 to 16 cm deep. Females dig nests in the early morning about 2 to 3 months after mating. They scratch or sniff at the ground as a means of testing the firmness of the soil, clay, or sand before excavating a nest and laying eggs. When digging, females may release a watery substance from an accessory gland to help loosen soil and allow for easier nest construction. Nest building can take up to 45 minutes. Females use their hind legs to push out soil contents, create a cylinder-shaped hole, and dig an incubation chamber within their holes. After releasing their eggs individually in 20-second to 4-minute intervals, females cover their nests with surrounding soil. Females use their limbs to pull in surrounding soil, and pack it down onto the nests. Female black-bellied slider stamp down the soil with their phalanges and slide the soil into place with their plastrons. This is done to ensure full coverage and safety of the eggs during incubation. (Bager and Freitas, 2007; Brejcha and Kleisner, 2015; Bujes, et al., 2011; Fagundes, et al., 2010; Kurzmann Fagundes, et al., 2010; Molina and Gomes, 1998; Tortato, et al., 2014)

Reproduction in black-bellied sliders occurs over a span of a year, with some females laying up to two clutches per season. Roughly two clutches with an interval of 43 days was recorded in a 2010 study. Black-bellied sliders display courtship behaviors from April to July, and time to egg-laying can take 55 to 104 days. Females store sperm, and thus it is unclear exactly when gestation begins. Nesting and egg-laying season occurs from September through February. Males can store sperm over a span of months while searching for a mate, and females can also halt their egg-laying process if needed. Black-bellied slider females typically halt the egg-laying process due to potential threats in the environment such as predators or poor weather conditions. They are iteroparous, and produce clutches of 6 to 19 eggs. The average weight of eggs is 14.9 g.

After laying their eggs and the covering their nests, female black-bellied sliders leave their clutches to incubate for 2 to 4 months, at which point they hatch. Newborn black-bellied sliders are completely independent at hatching.

While little is known regarding the rate of maturation of black-bellied sliders, habitats and resource availability are thought to play a role in this process. It is estimated that both sexes reach sexual maturity at 4 to 5 years old, although females may take 1 to 2 years longer. (Bager and Freitas, 2007; Brejcha and Kleisner, 2015; Bujes, et al., 2011; Fagundes, et al., 2010; Gradella and Helena, 2019; Kurzmann Fagundes, et al., 2010; Molina and Gomes, 1998; Seidel, 1989; Seidel, 1990; Tortato, et al., 2014)

  • Breeding interval
    recorded two clutches with an interval of 43 days (Fagundes, 2010)
  • Breeding season
    Mating season extends from April to July and nesting/egg-laying occurs September through February
  • Range number of offspring
    6 to 19
  • Average time to independence
    0 days
  • Range age at sexual or reproductive maturity (female)
    4 to 7 years
  • Range age at sexual or reproductive maturity (male)
    4 to 5 years

While male black-bellied sliders display no parental investment other than fertilization of ova, females play a substantial role in pre-ovulatory investment. Before laying eggs, females spend most of their time searching for food. They require energy not only for the production and laying of eggs, but for provisioning eggs with energy reserves. The yolk within eggs is composed of stored lipids and serves as an energy reserve for developing young. Non-polar lipids act as metabolic fuel for embryos as well as hatchlings. Eggs supplied with sufficient energy storage are considered independent the moment they are laid, but often reside in or near the same habitat as adults. (Nagle, et al., 1998)

  • Parental Investment
  • no parental involvement
  • female parental care
  • pre-hatching/birth
    • provisioning
      • female

Lifespan/Longevity

While the lifespan of black-bellied sliders has not been recorded, a close relative, red-eared sliders (Trachemys scripta) have been reported surviving up to 41.3 years in captivity. On average, red-eared sliders are expected to live up to 30 years in the wild, but their lifespan can be limited due to predation, parasitism, and pet trade trafficking by humans. (Castnet, 1994; Slavens and Slavens, 2018)

Behavior

Black-bellied sliders are terricolous and crepuscular, being most active in the morning and evenings. They are relatively sedentary and spend most of their time burrowing, hiding under vegetation, or basking. Basking frequency changes with weather and temperature. Black-bellied sliders bask more often during colder months and when water temperatures are low. Females search for food most actively after breeding season. Most of their time in water is spent in search of food, but may also be a way to evade predators. Black-bellied sliders are often found close to others when basking and have been observed in groups as large as eight individuals.

A report from 2010 noted that black-bellied sliders dug nests from 0600 to 1800 h, but digging was more common in morning hours. Nests were established, on average, 60.5 m from waterways (range: 0.4m to 160.5m). More specifically, 27.9% of all recorded nests were 25 to 50 m away from bodies of water. (Clavijo-Baquet and Magnone, 2017; Fagundes, et al., 2010; Grilo, et al., 2016; Kurzmann Fagundes, et al., 2010; Nordberg and McKnight, 2020; Santana, et al., 2014; Tortato, et al., 2014)

Home Range

The average home range of black-bellied sliders is 1.74 ha, with an estimated individual movement of 132 m per day. Black-bellied slider individuals are not known to defend a specific territory. (Grilo, et al., 2016)

Communication and Perception

All turtle species lack real eardrums, but instead have a tympanic disc with a sizable middle ear cavity. They use these discs to perceive sound underwater and above water. Their ears react to quieter sounds in water and work more effectively. Their tympanic discs may help black-bellied sliders navigate waterways, avoid predators, and find items to consume. Most communication between turtles can be described as screeching sounds, often louder and longer in duration with males. These sounds may be used to communicate a willingness to reproduce or some form of excitement.

Black-bellied sliders have complex visual mechanisms, using eyesight to orient themselves and navigate their environment. Black-bellied sliders have seven types of cones in their eyes, including one that perceives colors in the UV spectrum. It is undetermined whether they can perceive and interpret particular colors.

Black-bellied sliders do display tactile courtship behaviors such as biting, nudging, rubbing, stroking with fore claws, gulping, and head movements. (Brejcha and Kleisner, 2015; Christensen-Dalsgaard, et al., 2012)

Food Habits

Black-bellied sliders are omnivores, consuming vegetables, animals, and other organic matter. Diets of black-bellied sliders found in urban areas consist of a wider variety of food items compared to those found in rural areas. Examples of food items found in the diet of these turtles consist of green algae, roundworms (phylum Nematoda), giant salvinia (Salvinia molesta), and other animals in the groups Cladocera and Mollusca. Although they are considered a generalist species, vegetation is an important part of their diets. A study in 2019 reported that 85.3% of total ingested food items was vegetation. Another study from 2014 reported that many food groups such as macrophytes, crustaceans, and arachnids were only consumed by females. (Bager, et al., 2014; Silveira, et al., 2019)

  • Animal Foods
  • insects
  • mollusks
  • terrestrial worms
  • aquatic or marine worms
  • aquatic crustaceans
  • other marine invertebrates
  • Plant Foods
  • algae

Predation

A study from 2010 reported that predation rates of black-bellied sliders is low, with only a 3% risk of eggs being preyed upon within 24 hours post-nesting. This predation risk is primarily due to the odors associated with the liquid that females release during egg-laying. Predation of adult black-bellied sliders may vary depending on their size - smaller individuals are more likely to be preyed upon since they are easier to attack.

Besides pet trade trafficking by humans (Homo sapiens), the only predator reported to consume black-bellied sliders is Argentine black and white tegus (Tupinambis merianae). A study in 2016 reported deaths of black-bellied sliders as a result of black vultures (Coragyps atratus). Black-bellied sliders move rather slow and cannot escape threats easily, but their coloration may provide camouflage in their environment and help them evade predators. (Fagundes, et al., 2010; Kelehear, 2016)

  • Anti-predator Adaptations
  • cryptic

Ecosystem Roles

Black-bellied sliders are preyed upon most commonly by Argentine black and white tegus (Tupinambis merianae) and black vultures (Coragyps atratus). They are omnivores, meaning they consume a variety of both plant and animal matter.

Parasitic worms are commonly found in both sexes of black-bellied sliders, but these parasites are more abundant in females. Nematodes found in their stomachs included Spiroxys contortus, Falcaustra affinis, Camallanus emydidius, and Dioctophyme renale. Black-bellied sliders were also found to be hosts for trematodes including Telorchis corti, Telorchis achavali and monogeneans like Polystomoides rohdei, Neopolystoma and Temnocephala brevicornis. (Bernardon, et al., 2014; Kimmons and Moll, 2010; Mascarenhas, et al., 2021)

Commensal/Parasitic Species
  • Nematode (Spiroxys contortus)
  • Nematode (Falcaustra affinis)
  • Nematode (Camallanus emydidius)
  • Nematode (Dioctophyme renale)
  • Trematode (Telorchis corti)
  • Trematode (Telorchis achavali)
  • Monogenean (Neopolystoma)
  • Monogenean (Temnocephala brevicornis)

Economic Importance for Humans: Positive

Black-bellied sliders are highly sought after in the pet trade. Eggs are commonly stolen from nests in the wild and juveniles are frequently captured. They are then sold internationally and held as pets. Prices for black-bellied sliders as pets in Virginia were reported as $165 per juvenile. (Ackerman, 2022; Fagundes, et al., 2010; Kurzmann Fagundes, et al., 2010)

Economic Importance for Humans: Negative

Captive black-bellied turtles can carry Salmonella in their droppings. This bacterium can easily spread to humans and lead to infection. (CDC, 2020)

Conservation Status

Black-bellied sliders are not currently listed and have no special status on IUCN Red List, US Federal List, CITES, or the State of Michigan List.

Predation from other species is common, but humans may have the greatest impact on the survival of black-bellied sliders. Effects of the pet trade and habitat fragmentation place pressure on native populations of black-bellied sliders.

Black-bellied sliders are the most abundant turtles in southern Brazil. A conservation program was created in 1985 at the Sao Paulo Zoo in Brazil. This program allows for large-scale breeding of black-bellied sliders in captivity. By studying this program, zoologists can examine the reproductive behavior and development of black-bellied sliders for future reintroduction programs. As black-bellied sliders continue to be distributed through the pet trade, their release into the wild in new areas of the world increases their potential of becoming an invasive species. Areas outside of their natural habitat, such as the eastern United States have been noted to be a suitable living climate for black-bellied sliders. (Bager, et al., 2014; Fonseca, et al., 2021; Lisboa, et al., 2021; Molina, 1997)

Contributors

Triston Perry (author), Radford University, Sierra Felty (editor), Radford University, Bianca Plowman (editor), Radford University, Karen Powers (editor), Radford University, Victoria Raulerson (editor), Radford University, Christopher Wozniak (editor), Radford University, Galen Burrell (editor), Special Projects.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

Neotropical

living in the southern part of the New World. In other words, Central and South America.

World Map

acoustic

uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

causes disease in humans

an animal which directly causes disease in humans. For example, diseases caused by infection of filarial nematodes (elephantiasis and river blindness).

coastal

the nearshore aquatic habitats near a coast, or shoreline.

crepuscular

active at dawn and dusk

cryptic

having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.

diurnal
  1. active during the day, 2. lasting for one day.
ectothermic

animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature

female parental care

parental care is carried out by females

fertilization

union of egg and spermatozoan

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

freshwater

mainly lives in water that is not salty.

indeterminate growth

Animals with indeterminate growth continue to grow throughout their lives.

introduced

referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

natatorial

specialized for swimming

native range

the area in which the animal is naturally found, the region in which it is endemic.

omnivore

an animal that mainly eats all kinds of things, including plants and animals

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

pet trade

the business of buying and selling animals for people to keep in their homes as pets.

polygynandrous

the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

riparian

Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

social

associates with others of its species; forms social groups.

sperm-storing

mature spermatozoa are stored by females following copulation. Male sperm storage also occurs, as sperm are retained in the male epididymes (in mammals) for a period that can, in some cases, extend over several weeks or more, but here we use the term to refer only to sperm storage by females.

suburban

living in residential areas on the outskirts of large cities or towns.

swamp

a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.

tactile

uses touch to communicate

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

urban

living in cities and large towns, landscapes dominated by human structures and activity.

vibrations

movements of a hard surface that are produced by animals as signals to others

visual

uses sight to communicate

References

Ackerman, B. 2022. "Wholesale Exotic Pets" (On-line). Accessed March 29, 2022 at https://wholesaleexoticpets.com/shop/ols/products/xn-brazilian-black-bellied-slider-cb-baby-trachemys-dorbigni-kz92b.

Alcalde, L., N. Derocco, S. Rosset, J. Williams. 2012. Southernmost localities of Trachemys dorbigni and first record of Trachemys scripta elegans for Argentina (Cryptodira: Emydidae). Chelonian Conservation and Biology, 11/1: 128-133.

Bager, A. 2010. Trachemys dorbigni (Brazilian slider turtle): Albinism. Herpetological Bulletin, 113: 34.

Bager, A. 2010. Estimation of core terrestrial habitats for freshwater turtles in southern Brazil based on nesting areas. Journal of Herpetology, 44/4: 658-652.

Bager, A. 2014. Fidelity to nesting sites and orientation of Trachemys dorbigni (Duméril & Bibron, 1835) (Testudines: Emydidae) female in southern Brazil. Tropical Zoology, 25/1: 31-38.

Bager, A., T. Freitas. 2007. Nesting ecology of a population of Trachemys dorbignyi (Emydidae) in southern Brazil. Herpetologica, 63/1: 56-65.

Bager, A., C. Rosa, N. Piedras, A. Hahn. 2014. Dietary variation and overlap in D’Orbigny’s slider turtles Trachemys dorbigni (Duméril and Bibron1835) (Testudines: Emydidae). Journal of Natural History, 48/1: 1-8. Accessed January 31, 2022 at DOI: 10.1080/00222933.2013.840400.

Bernardon, F., A. Velente, G. Muller. 2014. Gastrointestinal helminths of Trachemys dorbigni Duméril & Bibron, 1835 (Testudines, Emydidae) from artificial urban ponds in southern Brazil. Pan-American Journal of Aquatic Sciences, 9/1: 54-57.

Brejcha, J., K. Kleisner. 2015. Turtles are not just walking stones: Conspicuous coloration and sexual selection in freshwater turtles. Biosemiotics, 9/1: 247-266.

Bujes, C., F. Molina, L. Verrastro. 2011. Population characteristics of Trachemys dorbigni (Testudines, Emydidae) from Delta Do Jacuí State Park, Rio Grande Do Sul, Southern Brazil. South American Journal of Herpetology, 6/1: 27-34.

CDC, 2020. "Outbreak of Salmonella Infections Linked to Pet Turtles" (On-line). Center for Disease Control and Prevention. Accessed March 29, 2022 at https://www.cdc.gov/salmonella/oranienburg-10-19/index.html.

Castnet, J. 1994. Age estimation and longevity in reptiles. Gerontology, 40/2: 174-192.

Christensen-Dalsgaard, J., C. Brandt, K. Willis. 2012. Specialization for underwater hearing by the tympanic middle ear of the turtle, Trachemys scripta elegans. Proceedings of The Royal Society B, 279/1739: 2816-2824.

Clavijo-Baquet, S., L. Magnone. 2017. Daily and seasonal basking behavior in two South American freshwater turtles, Trachemys dorbigni and Phrynops hilarii. Chelonian Conservation and Biology, 16/1: 62-69. Accessed January 31, 2022 at https://doi.org/10.2744/CCB-1201.1.

Cleiton, F., L. Giuliano-Caetano. 2008. Cytogenetic characterization of two turtle species: Trachemys dorbigni and Trachemys scripta elegans. nternational Journal of Cytology, Cytosystematics and Cytogenetics, 61/3: 253-257.

Czerwinski, M., A. Natarajan, L. Barske. 2016. A timecourse analysis of systemic and gonadal effects of temperature on sexual development of the red-eared slider turtle Trachemys scripta elegans. Developmental Biology, 420/1: 166-177.

Fagundes, C., A. Bager, S. Chechin. 2010. Trachemys dorbigni in an anthropic environment in southern Brazil: I) sexual size dimorphism and population estimates. Herpetological Journal, 20/1: 185-193.

Fonseca, É., C. Both, S. Cechin, G. Winck. 2021. Pet distribution modelling: Untangling the invasive potential of Trachemys dorbigni (Emydidae) in the Americas. Plos One, 16/1: e0259626. Accessed January 25, 2022 at https://doi.org/10.1371/journal.pone.0259626.

Gradella, A., M. Helena. 2019. Morphology and biometry of the reproductive organs of adult males of Trachemys scripta elegans reared in São Paulo state, Brazil 1. Pesquisa Veterinária Brasileira, 39/7: 538-548.

Grilo, C., A. Bager, T. Cardoso. 2016. Do the size and shape of spatial units jeopardize the road mortality-risk factors estimates?. Brazilian Journal of Nature Conservation, 14/1: 1-6.

Guidetti, Y., S. Ariel, A. Susana. 2015. Characterization of the genetic diversity of Trachemys dorbigni and Phrynops hilarii. Asian Herpetological Research, 6/3: 213-219.

Jackson, J., D. Starkey, R. Guthrie, M. Forstner. 2008. A mitochondrial DNA phylogeny of extant species of the genus Trachemys with resulting taxonomic implications. Chelonian Conservation and Biology, 7/1: 31-135.

Kelehear, C. 2016. Trachemys scripta elegans (Red-eared slider). Predation. Herpetology Review, 47/1: 129-130.

Kimmons, J., D. Moll. 2010. Seed dispersal by red-eared sliders (Trachemys scripta elegans) and common snapping turtles (Chelydra serpentina). Chelonian Conservation and Biology, 9/2: 289-294.

King, W., T. Krakuauer. 1966. The exotic herpetofauna of southeast Florida. Quarterly journal of The Florida Academy of Sciences, 29/2: 44-154.

Kurzmann Fagundes, C., A. Bager, S. Terezinha Zanini Cechin. 2010. Trachemys dorbigni in an anthropic environment in southern Brazil: II) Reproductive ecology. Herpetological Journal, 20: 195-199.

Lisboa, C., R. Vaz, L. Malagoli. 2021. Herpetofauna from an Atlantic forest fragment in São Paulo, Brazil. Herpetological Conservation and Biology, 16/2: 436-451.

Mascarenhas, C., M. Gertrud. 2015. Spiroxys contortus (Gnathostomatidae) and Falcaustra affinis (Kathlaniidae) from Trachemys dorbigni (Emydidae) in southern Brazil. Comparative Parasitology, 82/1: 129-136. Accessed January 31, 2022 at https://doi.org/10.1654/4726.1.

Mascarenhas, C., G. Muller. 2017. Camallanus emydidius n. sp. (Nematoda: Camallanidae) in Trachemys dorbigni (Duméril & Bibron, 1835) (Testudines: Emydidae) from Southern Brazil. International Journal for Parasitology: Parasites and Wildlife, 6/2: 108-114. Accessed January 31, 2022 at https://doi.org/10.1016/j.ijppaw.2017.04.004.

Mascarenhas, C., R. Silva, G. Muller. 2021. Helminth’s assemblage of Trachemys dorbigni (Testudines: Emydidae) in southern Brazil: implications of anthropogenic environments and host’s genders. Iheringia, Serie Zoologia, 111/1: 1-11.

Molina, F., N. Gomes. 1998. Breeding and nesting behaviour of d’orbigny’s slider turtle. International Zoo Yearbook, 36/1: 162-170.

Molina, F. 1997. Large-scale breeding of turtles at São Paulo Zoo: implications for turtle conservation in Brazil. J. Van Abbema (ed.), Proceedings: Conservation, Restoration, and Management of Tortoises and Turtles—An International Conference, none: 174–177.

Nagle, R., V. Burke, J. Congdon. 1998. Egg components and hatchling lipid reserves: Parental investment in kinosternid turtles from the southeastern United States. Comparative Biochemistry and Physiology, 120/1: 145-152.

Nordberg, E., D. McKnight. 2020. Nocturnal basking behavior in a freshwater turtle. Ecology, 101/7: e03048. Accessed April 12, 2022 at DOI:10.1002/ecy.3048.

Rodrigues, J., M. Coelho, J. Diniz-Filho. 2016. Exploring intraspecific climatic niche conservatism to better understand species invasion: The case of Trachemys dorbigni (Testudines, Emydidae). Hydrobiologia, 779: 127-134. Accessed January 31, 2022 at https://doi.org/10.1007/s10750-016-2805-8.

Santana, D., C. De-Carvalho, S. Rocha. 2014. Trachemys dorbigni (Duméril & Bibron, 1835) (Testudines: Emydidae) recorded in an artificial pond in northeastern Brazil. Herpetology Notes, 7/1: 211-213.

Seidel, M. 1990. Morphology and biometry of the reproductive organs of adult males of Trachemys scripta elegans reared in São Paulo state, Brazil 1. Journal of Herpetology, 24/2: 191-196.

Seidel, M. 1989. Trachemys dordigni (Dumeril and Bibron) Orbigny's slider. Catalogue of American Amphibians and Reptiles, 486: 1-3.

Siedel, M. 2002. Taxonomic observations on extant species and subspecies of slider turtles, genus Trachemys. Journal of Herpetology, 36/2: 285-292.

Silveira, E., C. Mascarenhas, F. Correa, G. Muller. 2019. Diet of Trachemys dorbigni (Duméril & Bibron, 1835) (Testudines: Emydidae) in anthropic environments from southern Brazil. Pan-American Journal of Aquatic Sciences, 14/1: 42-50.

Slavens, F., K. Slavens. 2018. "Frank and Kate's web page" (On-line). Accessed March 25, 2022 at http://www.pondturtle.com/.

Tortato, M., R. Bressan, T. Kunz. 2014. Reproduction of two exotic species of Trachemys Agassiz, 1857 (Testudines, Emydidae) at Parque Estadual da Serra do Tabuleiro, state of Santa Catarina, southern Brazil. Herpetology Notes, 7/1: 11-15.

Verrastro, L., C. Bujes. 2007. Supernumerary epidermal shields and carapace variation in Orbigny's slider turtles, Trachemys dorbigni (Testudines, Emydidae). Revista Brasileira de Zoologia, 24/3: 1-11.