The Brazilian snake-necked turtle (''Hydromedusa maximiliani'' ), locally known as ''cágado da serra'', and also commonly known as Maximilian's snake-necked turtle, is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

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

in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Chelidae. The species is

endemic Endemism is the state of a species being found 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 found else ...

southeastern Brazil The Southeast Region of Brazil ( pt, Região Sudeste do Brasil; ) is composed of the states of Espírito Santo, Minas Gerais, Rio de Janeiro and São Paulo. It is the richest region of the country, responsible for approximately 60% of the Brazilian ...

.Souza FL, Martins FI (2009). ''Hydromedusa maximiliani'' (Mikan, 1825) - Maximilian's Snake-Necked Turtle, Brazilian Snake-Necked Turtle. Chelonian Research Monographs 5 (26): 1-6. It is one of the smallest Brazilian freshwater turtles reaching a maximum straight carapace length of . The species prefers streams with sandy and rocky bottoms and clear water in forests above elevation.

Etymology

The specific name, ''maximiliani'', is in honor of German naturalist

Prince Maximilian of Wied-Neuwied Prince Alexander Philipp Maximilian zu Wied-Neuwied (23 September 1782 – 3 February 1867) was a German explorer, ethnologist and naturalist. He led a pioneering expedition to southeast Brazil between 1815–1817, from which the album ''Reise na ...

.Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). ''The Eponym Dictionary of Reptiles''. Baltimore: Johns Hopkins University Press. xiii + 296 pp. . (''Hydromedusa maximiliani'', p. 171).

Taxonomy

First described as ''Emys maximiliani'' by

Mikan ''Citrus unshiu'' is a semi-seedless and easy-peeling citrus species, also known as miyagawa mandarin, unshu mikan, cold hardy mandarin, satsuma mandarin, satsuma orange, naartjie, and tangerine. ''Citrus unshiu'' was named after Unshu (Wenzho ...

(1825), it was subsequently moved to the genus ''

Hydromedusa ''Hydromedusa'' is a turtle genus in the family Chelidae, commonly known as the South American snake-necked turtles. They are quite closely related to the South American side-necked swamp turtles (''Acanthochelys'') and the snake-necked turtles ...

'' by Wagler (1830). Wagler JG (1830). ''Natürliches System der Amphibien, mit vorangehender Classification der Säugthiere und Vögel''. Munich, Stuttgart and Tübingen: J.G. Cotta. vi + 354 pp. + one plate. (in German and Latin). Several other species described later have since been synonymized with this species. There are no recognised subspecies.

Description

The Brazilian snake-necked turtle is a small species reaching a straight carapace length of between with a weight of . The carapace of the adult is oval in shape varying in color from dark gray, through to dark or light brown. The plastron is a yellow or cream color. The species has a moderate-sized head with a small snout and yellowish jaws, with no barbels on the chin. The iris is black. The

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage * Dorsal c ...

surface of the head, neck and limbs are olive green to gray in color with a lighter cream-colored ventral surface.

Distribution and habitat

The Brazilian snake-necked turtle is endemic to

, in the states of

Bahia Bahia ( , , ; meaning "bay") is one of the 26 states of Brazil, located in the Northeast Region of the country. It is the fourth-largest Brazilian state by population (after São Paulo, Minas Gerais, and Rio de Janeiro) and the 5th-largest b ...

Minas Gerais Minas Gerais () is a state in Southeastern Brazil. It ranks as the second most populous, the third by gross domestic product (GDP), and the fourth largest by area in the country. The state's capital and largest city, Belo Horizonte (literally ...

Espírito Santo Espírito Santo (, , ; ) is a state in southeastern Brazil. Its capital is Vitória, and its largest city is Serra. With an extensive coastline, the state hosts some of the country's main ports, and its beaches are significant tourist attra ...

Rio de Janeiro Rio de Janeiro ( , , ; literally 'River of January'), or simply Rio, is the capital of the state of the same name, Brazil's third-most populous state, and the second-most populous city in Brazil, after São Paulo. Listed by the GaWC as a ...

and

São Paulo São Paulo (, ; Portuguese for ' Saint Paul') is the most populous city in Brazil, and is the capital of the state of São Paulo, the most populous and wealthiest Brazilian state, located in the country's Southeast Region. Listed by the Ga ...

. The distribution is associated with the mountainous Atlantic rainforest. As a generalization it is found in mountain streams above .Iverson JB (1992). ''A revised checklist with distribution maps of the turtles of the world''. Richmond, Indiana: Privately Printed. The species is found in shallow streams from in depth, with clear, cold water and sandy or rocky substrates.Souza FL (1995). "''História natural do cágado ''Hydromedusa maximiliani'' (Mikan, 1820) no Parque Estadual de Carlos Botelho, SP, região de Mata Atlântica (Reptilia, Testudines, Chelidae)''". Masters Thesis, Universidade Estadual Paulista, Rio Claro, SP, Brazil. (in Portuguese). Because of the dense canopy and closed understory of the forests the streams receive little sunlight making basking only possible in gaps along the stream.Yamashita C (1990). "''Hydromedusa maximiliani'' ecology". ''Herpetological Review'' 21: 19.

Conservation

Some populations of this species, ''H. maximiliani'', occur within protected areas and are hence afforded some protection from deforestation and pollution which are considered major threats. In regions outside these protected areas the species may be becoming fragmented and may therefore become increasingly vulnerable in the future.

References

"Hydromedusa maximiliani"
IUCN Red List of Threatened Species.1996 {{Taxonbar, from=Q2688237 Hydromedusa Reptiles of Brazil Endemic fauna of Brazil Reptiles described in 1825 Taxonomy articles created by Polbot