A bichir is any of about 10 species of air-breathing tropical fishes of the genus Polypterus , native to freshwater systems in western and central Africa. They have elongated bodies, fleshy lobes in their pectoral fins, rounded tails, and hard scales. Bichirs possess functional lungs, which they use to breathe air through two spiracles on the top of their heads, in addition to rudimentary gills that extract oxygen from the water. They live along the edges of streams and floodplains, remaining concealed by day and foraging at night for worms, aquatic insects, small fishes and amphibians. The Senegal bichir can propel itself across land for short distances. Male bichirs leap from the water and twist during courtship before they fertilize a female’s eggs.

Where do bichirs live?

Bichirs are native to freshwater ecosystems in western and central Africa. They inhabit river and lake systems. These fish typically live along the edges of streams and floodplains. Bichirs are sometimes harvested for food and kept in aquariums. The International Union for Conservation of Nature and Natural Resources considers all bichir species to be of least concern.

What does a bichir look like?

Bichirs are native to the freshwater systems of western and central Africa. They have elongated bodies, fleshy lobes on their pectoral fins, rounded tails, and hard, enameled scales. Their coloring is usually brown, grayish, or greenish on the upper body, with a white or yellowish underside. Most grow to be between 30 and 60 cm long, but some can reach up to 75 or even 97 cm. Bichirs possess functional lungs and rudimentary gills, breathing air through two spiracles on the top of their heads. The dorsal fin is a series of sharp spines, each with a flaglike cluster of fin rays. Senegal bichirs can use their pectoral fins to move across land for short distances.

How do bichirs breathe?

Bichirs, belonging to the genus Polypterus , are native to African freshwater systems and possess unique respiratory adaptations. They have functional lungs in addition to rudimentary gills. Bichirs breathe by taking air into their paired lungs through two spiracles on the top of their heads when they are at the water's surface. Their lungs are believed to be an ancient adaptation that arose in the Silurian Period. These lungs differ from those of other fishes, originating from a pouch on the ventral side, unlike the swim bladder.

How are bichirs different from other fish?

Bichirs are elongated tropical fishes, native to African fresh waters, with unique traits that set them apart from other fish. They have fleshy lobes on their pectoral fins, rounded tails, and hard, enameled scales. One key difference is their ability to breathe air using functional lungs, in addition to rudimentary gills. These lungs evolved from a pouch on the ventral side of the endoderm, unlike the swim bladders of other fishes, which developed on the dorsal side. Some species can even use their pectoral fins to move across land for short distances. Male bichirs also have a unique courtship ritual involving leaping from the water.

bichir

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Body plans of representative chondrostean fishes.

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Related Topics:: saddled bichir; Senegal bichir; Congo bichir

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bichir

fish

Also known as: Polypterus, lobefin

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What is a bichir?
A bichir is any of about 10 species of air-breathing tropical fishes of the genus Polypterus, native to freshwater systems in western and central Africa. They have elongated bodies, fleshy lobes in their pectoral fins, rounded tails, and hard scales.

Bichirs possess functional lungs, which they use to breathe air through two spiracles on the top of their heads, in addition to rudimentary gills that extract oxygen from the water. They live along the edges of streams and floodplains, remaining concealed by day and foraging at night for worms, aquatic insects, small fishes and amphibians. The Senegal bichir can propel itself across land for short distances. Male bichirs leap from the water and twist during courtship before they fertilize a female’s eggs.
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1. Definition of bichir
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Where do bichirs live?
Bichirs are native to freshwater ecosystems in western and central Africa. They inhabit river and lake systems. These fish typically live along the edges of streams and floodplains.

Bichirs are sometimes harvested for food and kept in aquariums. The International Union for Conservation of Nature and Natural Resources considers all bichir species to be of least concern.
2 Britannica Sources
1. Definition of bichir
2. bichir
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
What does a bichir look like?
Bichirs are native to the freshwater systems of western and central Africa. They have elongated bodies, fleshy lobes on their pectoral fins, rounded tails, and hard, enameled scales. Their coloring is usually brown, grayish, or greenish on the upper body, with a white or yellowish underside. Most grow to be between 30 and 60 cm long, but some can reach up to 75 or even 97 cm.

Bichirs possess functional lungs and rudimentary gills, breathing air through two spiracles on the top of their heads. The dorsal fin is a series of sharp spines, each with a flaglike cluster of fin rays. Senegal bichirs can use their pectoral fins to move across land for short distances.
1 Britannica Source
1. bichir
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How do bichirs breathe?
Bichirs, belonging to the genus Polypterus, are native to African freshwater systems and possess unique respiratory adaptations. They have functional lungs in addition to rudimentary gills.

Bichirs breathe by taking air into their paired lungs through two spiracles on the top of their heads when they are at the water's surface. Their lungs are believed to be an ancient adaptation that arose in the Silurian Period. These lungs differ from those of other fishes, originating from a pouch on the ventral side, unlike the swim bladder.
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2. bichir
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What do bichirs eat?
Bichirs are nocturnal predators inhabiting African freshwater systems. They forage along stream and floodplain edges, consuming worms, aquatic insects, small fishes and amphibians, and other small animals. The Senegal bichir can propel itself on land for short distances to hunt terrestrial insects or move between temporary ponds.
2 Britannica Sources
1. Definition of bichir
2. bichir
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
How are bichirs different from other fish?
Bichirs are elongated tropical fishes, native to African fresh waters, with unique traits that set them apart from other fish. They have fleshy lobes on their pectoral fins, rounded tails, and hard, enameled scales.

One key difference is their ability to breathe air using functional lungs, in addition to rudimentary gills. These lungs evolved from a pouch on the ventral side of the endoderm, unlike the swim bladders of other fishes, which developed on the dorsal side. Some species can even use their pectoral fins to move across land for short distances. Male bichirs also have a unique courtship ritual involving leaping from the water.
2 Britannica Sources
1. Definition of bichir
2. bichir
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

bichir, (genus Polypterus), any of about 10 species of air-breathing tropical fishes of the genus Polypterus native to freshwater river and lake systems in western and central Africa. Bichirs are classified in the family Polypteridae, order Polypteriformes.

These fishes are elongated in form with fleshy lobes in the pectoral fins, rounded tails, thick ganoid (hard, rhombic, enameled) scales, and functional lungs for breathing air (in addition to rudimentary gills used to extract oxygen from the water). The dorsal fin is a series of sharp spines, each with a flaglike end cluster of fin rays. The bichir’s upper body is brown, grayish, or greenish, the lower side often white or yellowish. Most species grow to between 30 and 60 cm (11.8 and 23.6 inches) long. Some members of the largest two species, the saddled bichirs (P. endlicherii) and Congo bichirs (P. congicus), grow to lengths of 75 cm (29.5 inches) and 97 cm (38.2 inches) and weights of 3.3 kg (7.3 pounds) and 4.4 kg (9.7 pounds), respectively.

Air at the water’s surface is taken into the bichir’s paired lungs through two spiracles on the top of its head. The bichir’s lungs, as well as those of reedfishes and extinct members of Polypteridae, are the result of an ancient adaptation that may have arisen late in the Silurian Period (443.8 million to 419.2 million years ago). The lungs of these fishes differ from lunglike breathing organs in other fishes, such as the tarpon, which are derived from the swim bladder (or air bladder, an organ that is used for buoyancy in most bony fishes). Polypterid lungs arose from the development of a pouch on the ventral (lower) side of the endoderm. The swim bladder, in contrast, developed along the dorsal (upper) side of the endoderm. Studies suggest that lung development began with the sarcopterygians, a group of primitive bony fishes thought to have given rise to the tetrapods (amphibians, reptiles, birds, and mammals).

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Bichirs live along the edges of streams and floodplains. They remain concealed by day and forage at night for worms, aquatic insects, small fishes and amphibians, and other animals. At least one species, the Senegal or gray bichir (P. senegalus), is capable of using its pectoral fins to propel itself across land for short distances—an adaptation that may have evolved to help the species move between temporary ponds that were drying up or hunt terrestrial insects.

Male bichirs leap from the water and twist and dart during courtship before they fertilize a female’s eggs. Bichirs apparently spawn in swamps and floodplains during the rainy season, and young fish have external branching gills and are newtlike in appearance.

Several species are harvested by humans for food and aquaria. All bichir species are considered species of least concern by the International Union for Conservation of Nature and Natural Resources.

Bichir classification is a matter of debate. Some researchers consider bichirs and the reedfish (Erpetoichthys calabaricus), its only living relative, to be chondrosteans (members of subclass Chondrostei) alongside sturgeons and paddlefishes. Others argue that bichirs may be more closely related to the crossopterygians (the group of lobe-finned fishes that includes living coelacanths). Most classifications, however, place them in their own clade, Cladistia, a sister group to subclass Chondrostei.