This document summarizes a preliminary survey of molluscan diversity in the Turag River in Tangi, Bangladesh. Thirteen species of molluscs across two classes were identified. The highest diversity was found in September, with most species (62%) belonging to the gastropod class. The three most common genera identified were Bellamya (23%), Lamellidense (15%), and Pila (15%). While the survey provided new information on molluscan diversity in the river, the author notes that deeper surveys using specialized equipment could uncover even greater diversity.

1. A PRELIMINARY SURVEY ON MOLLUSCAN
DIVERSITY IN THE RIVER TURAG AT TANGI, GAZIPUR;
BANGLADESH
SUBMITTED BY:
ROLL: M- 180604029
M.SC. (FISHERIES)
DEPARTMENT OF ZOOLOGY
SESSION: 2018-2019

2. Introduction:
 After insect, Mollusca is the second largest group of animals.
 The two major classes of molluscs have representatives in freshwater: the Gastropod and
the bivalve .
 There are many Genus and Species identified under the Class Gastropod and the bivalve.
 So far 22 freshwater mollusca have been recorded from Bangladesh.

3.  A Few reference book on freshwater molluscs of Indian
subcontinent has so far been available. Our knowledge of this
group is rather limited. Experts as well as students dealing with
freshwater molluscs are often handicapped by the absence of
any worthwhile guide book on the subject, (Dr. N. V. Subba Rao;
1989).
 The present handbook is aimed at filling this void and will serve
as a useful guide to all those interested.

4. Objectives:
There are very few works on freshwater mollusk in Bangladesh. It is not easy task for the
beginner to allocate collected specimens to the particular genus. Objectives can be
summarized as:
 To make a systematic survey of the freshwater mollusks of the TURAG River.
 To taxonomic study of collected Gastropods and Bivalves of the TURAG River.

5. Materials & Methods:
 Sampling Sites
 Name of the study sites : The Turag River
 Location : Tangi bazar area, Tangi,
Gazipur, Dhaka.
 Longitude : 90°24´29''E
 Latitude : 23°53´59''N
 Study area : 1 sq km.
 Study priod : April, 2019 to September, 2019.

6. Fig : Map of the study area Fig: View of the study area

7. Materials:
Fig : Digital Camera
Fig : Plastic bag Fig : Related book

8. Samples collection procedure
 Walking along the river banks and boat based survey were conducted.
 Specimens (live and died) were collected by hand picking.
 Collected samples were put in polythene bags and transported to the fisheries
laboratory, Department of Zoology, Jagannath University, Dhaka.

9. Identification:
 Identification work had done before colour faded away and based upon morphological
characteristics, basically colour of shell and external features.
 Following book have been followed for identification:

10. Result & Discussion :
8 species under 5 genera and 4 families of 2 orders under class Gastropoda
were identified in the present study.
Table: The identified Gastropods in the Turag River.
Order Family Genus & species English Name Local Name
Mesogastropoda
Viviparidae
Bellamya bengalensis River snail Dorakata Tokari
Bellamya crassa Pond snail Guli Shamuk
Bellamya dissimilis Pond snail Guli Shamuk
Pilidae
Pila globosa Common Apple-snail Bara Shamuk
Pila virens Apple snail Bara Shamuk
Thiaridae
Brotia costula Brotia snail Lomba Shamuk
Paludomus conica Canal snail Paba Shamuk
Basommatophora Planorbidae Gyrulaulus
convexiusculus
Horn snail Choto Pechano
Shamuk

11. 5 species under 4 genera and 3 families of 2 orders under class
Bivalvia were identified in the present study.
Table: The identified Bivalves in the Turag River
Order Family Genus & Species English Name Local Name
Unionoida Unionidae
Lamellidense
marginalis
Freshwater mussel Jhinuk
Lamellidense
jenkinsianus
Freshwater mussel Jhinuk
Parreysia
corrugata
Freshwater mussel Gol Jhinuk
Veneroida
Corbiculidae Corbicula
assamensis
Asian clam
Solecurtidae Novaculina
gangetica
Ganges clam Lomba jhinuk

12. The identified Gastropods
Bellamya bengalensis
Bellamya crassa

13. Bellamya dissimilis Pila globosa

14. Pila virens Brotia costula

15. Paludomus conica
Gyraius
convexiusculus

16. The identified Bivalves
Lamellidens
marginalis
Lamellidens
jenkinsianus

17. Parreysia corrugata Novaculina gangetica

18. Corbicula assamensis

19. Fig : Percentage of Gastropoda and Bivalvia
62%
38%
38%
Percentage of Class
Gastroda Bivalvia

20. Fig : Percentage of Genus
23%
15%
7%
8%
8%
15%
8%
8%
8%
Percentage of Genus
Bellamya
pila
Brotia
Paludomas
Gyrulaulus
Lamellidense
Parreysia
Corbicula
Novaculina

21. Conclusion:
 A total number of 13 species included in 2 classes under the phylum of
mollusca were identified from the River Turag near Tangi bazaar; Gazipur.
Highest number of species was recorded in September. The maximum
abundance of mollusc’s was found in June.
 About 62% of Class Gastropod and 38% of Class Bivalve are found as well
as Genus Bellamya were found in high rate about (23%), respectively
Lamellidense (15%) and Pila (15%) are also found in good number in this
study period.

22.  If diving equipment’s and research vessels facilities for deep
river collections are available, more specimens could be
collected as well as diversity could be more.
 The present study elucidated the molluscan diversity that
might be useful to investigate the contributions of these
macro invertebrates towards nutrient processing and explore
their role as bio monitors.
The study could provide new source of information for further
study leading to protection, culture projects and management
of our molluscs resources.

23. ANY QUESTION
???

24. THANK YOU