Amphibians watched the dinosaurs come and go, but today almost half of them are threatened with extinction. In 2010, Zoological Survey of India has documented a total of 311 amphibian species in India. Out of these 46 amphibian species are found in all 19 districts of West Bengal.
Links:
[1] http://admin.indiaenvironmentportal.org.in/feature-article/threat-amphibian-population-district-midnapore-west-bengal
[2] http://admin.indiaenvironmentportal.org.in/category/author/suman-pratihar
[3] http://admin.indiaenvironmentportal.org.in/category/journal/indian-forester-0
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/amphibians
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/medinipur-d
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/west-bengal
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/endangered-species