Labeo
Encyclopedia
Labeo is a genus of carp
Carp
Carp are various species of oily freshwater fish of the family Cyprinidae, a very large group of fish native to Europe and Asia. The cypriniformes are traditionally grouped with the Characiformes, Siluriformes and Gymnotiformes to create the superorder Ostariophysi, since these groups have certain...

s in the family Cyprinidae. They are found mainly in the Old World
Old World
The Old World consists of those parts of the world known to classical antiquity and the European Middle Ages. It is used in the context of, and contrast with, the "New World" ....

 tropics
Tropics
The tropics is a region of the Earth surrounding the Equator. It is limited in latitude by the Tropic of Cancer in the northern hemisphere at approximately  N and the Tropic of Capricorn in the southern hemisphere at  S; these latitudes correspond to the axial tilt of the Earth...

.

It contains the typical labeos in the subfamily Labeoninae
Labeoninae
Labeoninae is a doubtfully distinct subfamily of ray-finned fishes in the family Cyprinidae of order Cypriniformes. They inhabit freshwater and are most abundant in the region around southern China. They are a generally very apomorphic group, perhaps the most "advanced" of the Cyprinidae...

, which may not be a valid group, however, and is often included in the Cyprininae as tribe
Tribe (biology)
In biology, a tribe is a taxonomic rank between family and genus. It is sometimes subdivided into subtribes.Some examples include the tribes: Canini, Acalypheae, Hominini, Bombini, and Antidesmeae.-See also:* Biological classification* Rank...

 Labeonini. If the Labeoninae are accepted as distinct, Labeonini is the name of the tribe in this subfamily to which the labeos belong. If the Labeonini are considered a tribe of the Cyprininae, the labeos are placed in subtribe Labeoina.

The labeos appear fairly similar to the "freshwater shark
Freshwater shark
True freshwater sharks are sharks able to live in freshwater lakes and rivers, including:* the bull shark, Carcharhinus leucas, which swims up tropical rivers around the world...

s" of the genus Epalzeorhynchos
Epalzeorhynchos
Epalzeorhynchos is a small ray-finned fish genus of the family Cyprinidae. Its members are – like some other cyprinids – known as "freshwater sharks" or simply "sharks". They are, however, freshwater members of the Osteichthyes lineage which is distinct from the Chondrichthyes lineage...

, which is also part of the Labeoninae (or Labeonini), but is not very closely related. Labeos are larger, and have a more spindle
Spindle (textiles)
A spindle is a wooden spike used for spinning wool, flax, hemp, cotton, and other fibres into thread. It is commonly weighted at either the bottom middle or top, most commonly by a circular or spherical object called a whorl, and may also have a hook, groove or notch, though spindles without...

-shaped body, as they are mostly free-swimming rather than benthic like Epalzeorhynchos. Their mouths look very different, too; they have a pronounced rostral cap, which covers the upper lip except when feeding. The lips are expanded into thick, sausage
Sausage
A sausage is a food usually made from ground meat , mixed with salt, herbs, and other spices, although vegetarian sausages are available. The word sausage is derived from Old French saussiche, from the Latin word salsus, meaning salted.Typically, a sausage is formed in a casing traditionally made...

-shaped pads which have keratin
Keratin
Keratin refers to a family of fibrous structural proteins. Keratin is the key of structural material making up the outer layer of human skin. It is also the key structural component of hair and nails...

ized edges. Thus, their mouth parts are moderately apomorphic; not as little-developed as in barbs or in Epalzeorhynchos, but neither as extensive as in, for example, Garra
Garra
Garra, the garras, are a genus of ray-finned fish in the family Cyprinidae. These fish are one example of the "log suckers", sucker-mouthed barbs and other cyprinids commonly kept in aquaria to keep down algae...

or Ptychidio. Labeos have the two barbel
Barbel (anatomy)
A barbel on a fish is a slender, whiskerlike tactile organ near the mouth. Fish that have barbels include the catfish, the carp, the goatfish, sturgeon, the zebrafish and some species of shark...

s on the rostrum
Rostrum (anatomy)
The term rostrum is used for a number of unrelated structures in different groups of animals:*In crustaceans, the rostrum is the forward extension of the carapace in front of the eyes....

 which are common among the Cyprinidae, and also another pair of barbels at the rear edges of the lower maxilla, which has been lost in some of their relatives. They have a well-developed vomeropalatine organ. In the Weberian apparatus
Weberian apparatus
The Weberian apparatus is an anatomical structure that connects the swim bladder to the auditory system in fishes belonging to the Superorder Ostariophysi. When it is fully developed in adult fish, the elements of the apparatus are sometimes collectively referred to as the Weberian ossicles...

, the posterior supraneural bone is elongated and contacts the skull
Skull
The skull is a bony structure in the head of many animals that supports the structures of the face and forms a cavity for the brain.The skull is composed of two parts: the cranium and the mandible. A skull without a mandible is only a cranium. Animals that have skulls are called craniates...

 at the forward end.


Species

Over one hundred different Labeo species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

are known to date. New ones are being described every few years or so.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK