''Nilssonia'' is a
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
of
softshell turtle
The Trionychidae are a taxonomic family of a number of turtle genera, commonly known as softshell turtles. The family was erected by Leopold Fitzinger in 1826. Softshells include some of the world's largest freshwater turtles, though many can a ...
s (
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
Trionychidae) from rivers, streams, ponds, and lakes in
South Asia
South Asia is the southern subregion of Asia, which is defined in both geographical and ethno-cultural terms. The region consists of the countries of Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, and Sri Lanka.;;;;;;;; ...
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 "unispec ...
, 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, pleural space, or interpleural space is the potential space between the pleurae of the pleural sac that surrounds each lung. A small amount of serous pleural fluid is maintained in the pleural cavity to enable lubrication bet ...
scale pair of the bony
carapace
A carapace is a Dorsum (biology), 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 tor ...
, 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
The Indian softshell turtle (''Nilssonia gangetica''), or Ganges softshell turtle is a species of softshell turtle found in South Asia in rivers such as the Ganges, Indus and Mahanadi. This vulnerable turtle reaches a carapace length of up to ...
(''A./N. gangeticus'') and the
Leith's softshell turtle
Leith's softshell turtle (''Nilssonia leithii'') is a species of turtle in the family Trionychidae. The species is found in peninsular Indian rivers including the Bhavani, Godavari, and Moyariii Rivers. The types.... locality is Pune in India.
...
(''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
The Indian softshell turtle (''Nilssonia gangetica''), or Ganges softshell turtle is a species of softshell turtle found in South Asia in rivers such as the Ganges, Indus and Mahanadi. This vulnerable turtle reaches a carapace length of up to ...
'' – Indian softshell turtle, Ganges softshell turtle
*''
Nilssonia hurum'' – Indian peacock softshell turtle
*''
Nilssonia leithii'' – 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