Nilssonia nigricans
Silhouette: Armin Reindl · PhyloPic
In 3 days ~70% in a week ~90%
The black softshell turtle or Bostami turtle or Mohan (Nilssonia nigricans), previously placed in genus Aspideretes, is a species of freshwater turtle found in India (Assam, Tripura and West Bengal) and Bangladesh (Chittagong and Sylhet). It was long believed to consist of inbred individuals of the Indian softshell turtle (N. gangetica) or the Indian peacock softshell turtle (N. hurum), but while it is a close relative of the latter, it is a distinct species.
In the 1800s, it was believed these turtles were brought from Iran to Chittagong shrine pond by Hazrat Bayezid Bostami. This turtles that he had brought to this pond were treated as sacred and respected by the public. It was also believed by following local tales related to the turtle, about the turtles once being Jinns (a mythological creature in Islam).
Previously declared extinct by the International Union for Conservation of Nature in 2002, these turtles were found still to exist in a temple's pond called the Hayagriva Madhava Temple located in Assam, and in Kalyan Sagar lake in Tripura Sundari Temple in Udaipur, Tripura, India. Through conservation methods and protection of the species, some of these turtles can be found today throughout the wild, and scientists and environmental biologists are continuing to work hard to preserve this endangered species and their natural habitat. Their mitogenome represents relatedness to 19 other species of the Testudines. Nilssonia nigricans is the sister species of Nilssonia formosa. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Kaziranga National Park | 🇮🇳 India |
More parks will be added in future updates.
No species of the same family or order lives in Kaziranga National Park, so these are its closest relatives here: other reptiles.
Possible
About 30% of wildlife watchers report a Black Soft-shell Turtle sighting in Kaziranga National Park on a given day, based on 9 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 7th most-seen of the 8 reptiles we can rate there. Over three days the chance rises to about 70%, and over a week to about 90%, if each day is a fresh chance.
July and August
In those months about 60% of wildlife watchers report a Black Soft-shell Turtle in Kaziranga National Park on a given day, against under 5% in January, May and November, the lowest months. Those are among Kaziranga National Park's wettest months, with about 390 mm of rain a month against 10 mm in December.
Between 11 am and 2 pm
Across all the parks we cover, that three-hour window holds the most Black Soft-shell Turtle sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Only Kaziranga National Park, in our data
Kaziranga National Park is the only park on Wallace's Line with enough records to rate Black Soft-shell Turtle sightings: about 30% of wildlife watchers there report one on a given day.
GBIF citizen-science records
It is estimated from how often the Black Soft-shell Turtle is recorded against all the reptiles logged in Kaziranga National Park (9 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
