''Nilssonia'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

softshell turtle Trionychidae is a family of turtles, commonly known as softshell turtles or simply softshells. The family was described by Leopold Fitzinger in 1826. Softshells include some of the world's largest freshwater turtles, though many can adapt to li ...

s (

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 ...

Trionychidae) from rivers, streams, ponds, and lakes in

South Asia South Asia is the southern Subregion#Asia, subregion of Asia that is defined in both geographical and Ethnicity, ethnic-Culture, cultural terms. South Asia, with a population of 2.04 billion, contains a quarter (25%) of the world's populatio ...

and Burma. In many treatments, it is

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

, with the single species Burmese peacock softshell (''N. formosa''). However, the supposed other genus of peacock softshells, ''Aspideretes'', is more closely related to ''N. formosa'' than had been believed. They differ only in the neural plates between the first

pleural The pleural cavity, or pleural space (or sometimes intrapleural space), is the potential space between the pulmonary pleurae, pleurae of the pleural sac that surrounds each lung. A small amount of serous fluid, serous pleural fluid is maintained ...

scale pair of the bony

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 ...

, which are fused into one in ''N. formosa'' and unfused in the others. (2007). "Genetic evidence for wild-living ''Aspideretes nigricans'' and a molecular phylogeny of South Asian softshell turtles (Reptilia: Trionychidae: ''Aspideretes, Nilssonia'')". '' Zool. Scripta'' 36 (4): 301–310. (HTML abstract) Thus, it has been proposed to unite the two genera under the older name, ''Nilssonia''. As it seems, the closest living relatives of the Burmese peacock softshell are the Indian softshell turtle (''A./N. gangeticus'') and the Leith's softshell turtle (''A./N. leithii''), making the merging of the genera well warranted.

Etymology

The generic name, ''Nilssonia'', is in honor of Swedish zoologist Sven Nilsson.Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). ''The Eponym Dictionary of Reptiles''. xiii + 296 pp. . ("Nilsson", p. 191).

Species

If the genera are united, the five species are: *'' Nilssonia formosa'' – Burmese peacock softshell, Burmese softshell turtle *'' Nilssonia gangetica'' – Indian softshell turtle, Ganges softshell turtle *'' Nilssonia hurum'' – Indian peacock softshell turtle *''

Nilssonia leithii Leith's softshell turtle (''Nilssonia leithii)'' is a species of turtle in the Family (biology), family Trionychidae. The species is found in peninsular Indian rivers including the Tungabhadra River, Thungabhadra, Ghataprabha River, Ghataprabha, ...

'' – Leith's softshell turtle, Nagpur softshell turtle *'' Nilssonia nigricans'' – black softshell turtle, Bostami turtle

References

{{DEFAULTSORT:Nilssonia (Animal) Turtle genera Taxa named by John Edward Gray Taxonomy articles created by Polbot