External Morphology of Rohu or Labeo rohita (With Diagram)

Labeo rohita is a particular breed of fish belonging to the carp family which is found in rivers all around South Asia. It is also known as the Rohu, Rui, Ruhi, or Roho labeo. It is a substantial omnivore that is widely cultivated. In this article, we will look into the classification, geographical distribution, habitat, ecology, characteristics, and economic importance of Labeo rohita.

What is Labeo rohita?

The Rohu or Labeo rohita is a big, silvery-colored fish with a prominently arched head. It is typically found in ponds and rivers. Due to the way that Rohu feeds, it is frequently cultivated with the bottom-feeding Cirrhina mrigala and the surface-feeding Catla catla.

Diagram of Labeo rohita

The labeled diagram of Labeo rohita is shown below:

👁 Labeo-rohita

Classification of Labeo rohita

Geographical Distribution

The Rohu is a river-dwelling species that is present in many rivers in northern, central, and eastern India, Pakistan, Vietnam, Bangladesh, Nepal, and Myanmar. It has also been introduced into a few rivers in peninsular India and Sri Lanka.

Habitat

In rivers and ponds, Labeo rohita can be found in great abundance. They are vegetarians and bottom feeders. They occasionally consume animal foods. It is raised alongside Cirrhina mrigala and Catla catla because of their feeding habits. Only rivers and bund-style tanks are suitable for Rohu breeding; restricted waterways are not suitable.

Ecology

The species is omnivorous and exhibits distinct feeding preferences at various life stages. It consumes mostly zooplankton at the beginning of its life cycle, but as it grows, it consumes an increasing amount of phytoplankton. As an adult or juvenile, it is a herbivorous column feeder that consumes primarily phytoplankton and submerged vegetation. It appears to feed by sieving the water based on the modification of its thin, hair-like gill rakers.

Rohu sexually matures between the ages of two and five. In the monsoon season, they typically spawn by staying in the middle of overflowed rivers above tidal reach. The southwest monsoon typically coincides with Rohu's spawning season. It is possible to gather spawn from rivers and raise it in tanks and lakes.

General Characteristics of Labeo Rohita

The following are the characteristics of labeo rohita:

1. Carp and Rohu are two frequent names for Labeo rohita in Hindi.
2. The body is fusiform, compressed, and roughly 1 meter long. It weighs 4 kg.
3. The color of the body is silvery white underneath and bluish or brownish on the back. Large, overlapping cycloid scales cover the body. Scales are crucial for taxonomic purposes.
4. The head, trunk, and tail are the different body regions.
5. The head is compressed, producing a nose that is short, obtuse, and blunt. It has soft upper and lower lips that surround a sub-terminal mouth with fringed lips. It also has paired eyes and paired nostrils.
6. From the upper lip, two filamentous barbels grow. The nose is rectangular, flattened, bloated, and projects beyond the jaws. It is covered in little tubercles.
7. A large operculum that encloses the branchial chamber and gills hangs on either side.
8. A distinct lateral line exists. Tubes of the lateral line system perforate the scales that cover the lateral line. Cycloid scales are described as flat, bony, with rounded edges. They combine to create a seamless coating.
9. Soft fin rays are present on the dorsal, anal, and caudal fins, which are paired. Equal lobes of the caudal fin are forked.
10. Between the bladder and the inner ear, there is a Weberian apparatus. Mesonephric kidneys exist.

Economic Importance of Labeo Rohita

Omega 3 fatty acids, Vitamin A, Vitamin B, and Vitamin C are all abundant in Rohu. Additionally, it contains a lot of Vitamin D, a vitamin that is only found in a few foods. Eating fish helps prevent osteoporosis, a disease caused by a lack of Vitamin D. In Bangladesh, Nepal, and Pakistan, as well as the Indian states of Tripura, Nagaland, Bihar, Odisha, Assam, West Bengal, Andhra Pradesh, Tamil Nadu, and Uttar Pradesh, Rohu is a very popular meal consequently boosting the economies of the listed states. The state government of Bihar is now working to add the fish to the List of Geographical Indications in India (GI).