B. bagarius (Hamilton, 1822) is a fish species that has huge potential as food and game fish in Bangladesh, Bhutan, India, and Nepal, but is encountering the threat of extinction in Bangladesh and throughout the world, which can be inferred from its alarming conservation status in Bangladesh as well as throughout the world. It is known as “Baghair” or “Bagh mach” in Bangladesh. In Bangla, the term “Bagh” refers to a tiger.
1. Biological Features, Ecology, and Population Trends
1.1. Identification
B.B. bagarius bagarius has an elongated and flat body, and it is flattened up to the pelvics
[1]. For convenience, it is divided into three body parts:
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-
- a.
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Head region:-
- Head region: i.
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It has a large, osseous, and naked head which is greatly depressed, and its snout is sharply conical without pointing - It has a large, osseous, and naked head which is greatly depressed, and its snout is sharply conical without pointing
[2].-
- . ii.
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It occupies a ventral, wide, and crescentic mouth - It occupies a ventral, wide, and crescentic mouth
[3]- with thick lips and sharp, unequal teeth, which are organized into bands on the jaws
[2]- . They occupy dorso-ventrally flattened buccal cavity and pharynx
[4].-
- . iii.
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Its eyes are small and placed dorsally - Its eyes are small and placed dorsally
[2]- ; a membranous fold separates the closely placed nostrils
[5].-
- . iv.
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It has four pairs of barbells. One pair is maxillary, with stiff and broad bases, one pair is tiny nasal, and the remaining two pairs are mandibular barbell - It has four pairs of barbells. One pair is maxillary, with stiff and broad bases, one pair is tiny nasal, and the remaining two pairs are mandibular barbell
[2][5].-
- . v.
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Its gill openings are wide - Its gill openings are wide
[5]- ; gill membranes are free from each other and attached with the isthmus base
[2][5]- . It has 4–8 elongated neural spines and 6–9 gill rakers
[6].-
- .
-
-
- b.
-
Middle region:-
- Middle region: i.
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They bear no scales but have a myriad of pentagonal epidermal elevations on their skin that give a rough feel on touch - They bear no scales but have a myriad of pentagonal epidermal elevations on their skin that give a rough feel on touch
[7]- . Their skin is also equipped with flask-shaped mucous glands that secrete either acidic or neutral mucopolysaccharides as mucous
[7].-
- . ii. Their bodies are attractively light yellowish or greyish in color, with large messy black bands.
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Their bodies are attractively light yellowish or greyish in color, with large messy black bands. These bands cover the dorsal and adipose fin bases - These bands cover the dorsal and adipose fin bases