Small Size Gastropod Fauna from the Matli Geothermal Spring, Bhagirathi Valley, Garhwal Himalaya, Uttarakhand: Ecological Implications

• Published in: Journal of the Geological Society of India Vol. 98; no. 1; pp. 47 - 52
• Main Authors: Chatterjee, Nikitasha, Gupta, Anil K., Tiwari, Sameer K., Clemens, Steven C., Sharma, Kanishak
• Format: Journal Article
• Language: English
• Published: New Delhi Geological Society of India 2022; Springer Nature B.V
• Subjects: Abundance; Earth and Environmental Science; Earth Sciences; Freshwater; Freshwater molluscs; Geology; Geothermal springs; Habitats; Hydrogeology; Inland water environment; Lymnaea; Marine molluscs; Mollusks; Nutrients; Original Article; Physiological effects; Physiological factors; Rivers; Snails; Spring; Spring (season); Spring water; Water analysis; Water sampling; Water springs; Watersheds
• ISSN: 0016-7622; 0974-6889
• DOI: 10.1007/s12594-022-1926-0

The occurrence of freshwater molluscs in the geothermal springs is reported by numerous workers in different parts of the world. However, reports of such occurrences in the Indian subcontinent are either scanty or are not available in the published literature. In this study, a swarm of small size gastropod community have been encountered in the vicinity of Matli geothermal spring, which is located on the right bank of the downstream Bhagirathi river in the Garhwal Himalaya in Uttarakhand, India. Gastropod samples were collected from 3 locations near the spring and water samples were collected from the spring and the river. The samples were identified as belonging to the species Lymnaea acuminata Lamarck, 1822 according to their form and habitat. The abundance, size and thickness of the snails were higher near the spring than near the Bhagirathi river. The δ 18 O shell and δ 13 C shell values of all the bulk samples range from − 8.2 to − 7.8‰ (VPDB) and from − 9.5‰ (VPDB) to − 6.5‰ (VPDB), respectively. Since the temperature of the geothermal spring remains constant irrespective of seasons, no significant intra-shell variation in δ 18 O shell is observed, while intra—shell δ 13 C shell values show significant variation reflecting season change. Lymnaea accuminata is originally a freshwater gastropod which is found all along the Ganga-Brahmaputra watersheds. This species prefers a habitat near the geothermal spring owing to the abundance of nutrients in spring water and other physiological factors.