Carp is the name applied both to a large species of fish (Cyprinus carpio) and to the family (Cyprinidae) of which it is a member.
The largest member of the carp family and the typical form, Cyprinus carpio, grows to a length of about 40 inches (1 meter) and a weight of about 70 pounds (32 kg) in Europe and Asia. In Britain and North America, however, its maximum weight is around 45 pounds (20 kg). The carp is a narrow fish with a broad oval cross section and a very long dorsal fin. The dorsal fin and the anal fin
have a stout serrated first ray. Four barbels surround a moderate-sized, toothless mouth. The color varies from a muddy brown to olive or coppery brown. The lower fins are often red. Wild carp usually have scales that are regularly arranged and overlapping, but there is considerable variation in scales among the great many varieties of the species. The mirror carp, for example, has a few extremely large scales, while the leather carp has only a few small scales along the base of the dorsal fin.In common with other members of the family, the common carp has a number of interesting anatomical features. For example, it has pharyngeal, or throat, teeth (rather than teeth on the jaws). These grind food against a hard pad on the lower part of the skull. The fish also has a group of unique bones, called Webberian ossicles, that connect the air bladder to the middle ear.
Behavior
The carp thrives best in large bodies of warm, quiet water, but it lives in rapid rivers as well. Large carp are very active in shallow water in the spring. Their activity is usually obvious since they swirl and jump, muddying the water. Carp feed on aquatic insects, snails, crustaceans, aquatic vegetation, organic waste, and to a lesser extent on the eggs and young of other fishes when they are abundant. Because of their omnivorous diet, carp were once used in sewage treatment in Europe.
The carp spawns in late spring. Its eggs adhere to vegetation and are not cared
for. Some carp have lived for over 40 years in captivity. However, wild carp probably only live for 12 to 15 years.Habitat
The original habitat of the carp was probably the region from the Amur River in northeastern Asia to Myanmar (Burma) and westward to the Black, Caspian, and Aral seas. In the hope of providing a readily available and cheap food supply, it was introduced into many other regions. The carp was introduced into eastern Europe before the Christian era. It was then taken to Britain and in the late 19th century was introduced into North America, where it quickly became widely distributed.
Economic Importance
In Europe and Asia, carp are netted in large numbers and cultivated extensively for food. In North America large numbers are captured by commercial fishermen, but carp has never been highly prized for food there except by recent emigrants from Europe. In North America, it has only recently been angled to any extent. Carp is thought to be destructive to its habitat and harmful to other fishes inhabiting the same area because of its "rooting" behavior (its tendency to dig up the earth with its snout) and omnivorous eating habits.
Carp Family
The carp family, often referred to as the minnow family in North America, comprises some 1,500 species, which occur throughout the Northern Hemisphere. The family is classified in the order Cypriniformes (Ostariophysi). Among the members of the family are the bitterling, bream, bleak, chub, and goldfish. The wild goldfish, Carassius auratus, and its many derivatives, such as the crucian carp and the golden carp, are closely related to the carp, Cyprinus carpio. Both the carp and the goldfish have been selectively bred for so long—both as food fishes and as ornamental fishes—that a confusing complex of varieties now exists.
Reference: E.J. Crossman, “Carp” University of Toronto