Ruhi fish looks long, squishy and mace-shaped. Such structure is called streamlined. It is silvery white in color. They are over three feet tall and can weigh 20-25 kg. The body of roe fish consists of three parts. Head, body and tail
1. Head: The part from the tip of the body to the neck is called the head. The surface of the head is convex, smooth and free from scales. A semi-circular mouth hole is located just below the head. The mouth is surrounded by fleshy lips. On either side of the mouth opening are thread-like sensory maxillary barbels. There are two eyes on either side of the head. There is no pallava in the eyes. There is one nostril in front of the eyes. Each side has a large movable kanko. Beneath the kanko are four comb-like gills. At the free end of the conch there is a thin bronchiostigmal membrane.
2. Body: The part from the back of the fin to the anus is called the body. It is the largest part of the body. On either side of the body there are two lateral lines from tip to tail. It is called sensory side line because it contains sensory cells. It contains numerous lateral line organs or neuromasts. The body of ray fish has even and odd fins. These are a pair of pectoral fins, a pair of pelvic fins, a large dorsal fin and an anal fin. The stem is covered with thin cycloid scales. There are three tiny pores on the base of the body. Anus, genitals and rectal pores. Dr. Siddiq Publications
3. Tail: The end of the body from the anus is called the tail. At the tip of the tail is a homocircular caudal fin. It is divided into two parts. Super-symmetric and Semi-symmetric. The tail has 6 fins. Tail fin is the only moving part of fish.