Nilssonia leithii
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Testudines
Suborder: Cryptodira
Family: Trionychidae
Subfamily: Trionychinae
Genus: Nilssonia
Gray, 1872[1]
  • See text
  • Nilssonia Gray, 1872: 332[1]
  • Isola Gray, 1873: 51[3]
  • Aspideretes O.P. Hay, 1904: 274[4]

Nilssonia is a genus of softshell turtles (family Trionychidae) from rivers, streams, ponds, and lakes in South Asia and Burma. In many treatments, it is monotypic, 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 scale pair of the bony carapace, which are fused into one in N. formosa and unfused in the others.[5]

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.[5][2]


The generic name, Nilssonia, is in honor of Swedish zoologist Sven Nilsson.[6]


If the genera are united, the five species are:


  1. ^ a b Gray, John Edward (1872). "Notes on the mud-tortoises of India (Trionyx, Geoffroy)". Annals and Magazine of Natural History, Fourth Series 10: 326–340.
  2. ^ a b Turtle Taxonomy Working Group [van Dijk PP, Iverson JB, Rhodin AGJ, Shaffer HB, Bour R] (2014). "Turtles of the world, 7th edition: annotated checklist of taxonomy, synonymy, distribution with maps, and conservation status". In: Rhodin AGJ, Pritchard PCH, van Dijk PP, Saumure RA, Buhlmann KA, Iverson JB, Mittermeier RA (editors) (2014). "Conservation Biology of Freshwater Turtles and Tortoises: A Compilation Project of the IUCN/SSC Tortoise and Freshwater Turtle Specialist Group". Chelonian Research Monographs 5 (7): 000.329–479, doi:10.3854/ crm.5.000.checklist.v7.2014.
  3. ^ Gray, John Edward (1873). "Notes on mud-tortoises (Trionyx, Geoffroy), and on the skulls of the different kinds". Proceedings of the Zoological Society of London 1873: 38–72.
  4. ^ Hay, Oliver P. (1904). "On the existing genera of the Trionychidae". Proceedings of the American Philosophical Society 42: 268–274.
  5. ^ a b Praschag P, Hundsdörfer AK, Reza AHMA, Fritz U (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. doi:10.1111/j.1463-6409.2007.00282.x (HTML abstract)
  6. ^ Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). The Eponym Dictionary of Reptiles. xiii + 296 pp. ISBN 978-1-4214-0135-5. ("Nilsson", p. 191).