Iberian Barbel
Encyclopedia
The Iberian Barbel is a ray-finned fish 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...

 in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Cyprinidae. It is here placed in Luciobarbus
Luciobarbus
Luciobarbus is a somewhat disputed genus of ray-finned fishes in the family Cyprinidae. Its species are mainly found around the Mediterranean region. Its type species is the Mangar , for which the genus was established by Heckel in 1843...

following the IUCN, but that genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 is very closely related to the other typical barbels and perhaps better considered a mere subgenus
Subgenus
In biology, a subgenus is a taxonomic rank directly below genus.In zoology, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the generic name and the specific epithet: e.g. the Tiger Cowry of the Indo-Pacific, Cypraea tigris Linnaeus, which...

 of Barbus
Barbus
Barbus is a ray-finned fish genus in the family Cyprinidae. The type species of Barbus is the Common Barbel, first described as Cyprinus barbus and now named Barbus barbus...

. This large barbel can grow to over 50 cm (19.7 in) long.

Natural hybrids of this barbel and the closely related L. bocagei are not uncommon in the middle Tagus river. The two species and their hybrids are hard to distinguish, but L. comizo has a longer and nore narrow, and the last unbranched ray of the dorsal fin
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...

 has a longer denticulated section but with more widely-spaced denticles. In the first two traits the hybrids are intermediate between their parent species, in the latter they are closer to the Iberian Barbel. Also, the two species are distinguished by their microhabitat preferences where they are sympatric, with L. bocagei inhabiting somewhat faster-moving parts of the river. The hybridisation confounds phylogenetic studies based only on mtDNA.

L. comizo is endemic to the Iberian Peninsula
Iberian Peninsula
The Iberian Peninsula , sometimes called Iberia, is located in the extreme southwest of Europe and includes the modern-day sovereign states of Spain, Portugal and Andorra, as well as the British Overseas Territory of Gibraltar...

, where it occurs in both Portugal
Portugal
Portugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...

 and Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...

. It inhabits the slow-moving middle and lower parts of river
River
A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...

s and reservoir
Reservoir
A reservoir , artificial lake or dam is used to store water.Reservoirs may be created in river valleys by the construction of a dam or may be built by excavation in the ground or by conventional construction techniques such as brickwork or cast concrete.The term reservoir may also be used to...

s in the Tagus
Tagus
The Tagus is the longest river on the Iberian Peninsula. It is long, in Spain, along the border between Portugal and Spain and in Portugal, where it empties into the Atlantic Ocean at Lisbon. It drains an area of . The Tagus is highly utilized for most of its course...

' and the Guadiana Rivers' drainage basin
Drainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...

s. Its habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...

 are deep and almost stagnant waters with abundant aquatic
Aquatic plant
Aquatic plants are plants that have adapted to living in aquatic environments. They are also referred to as hydrophytes or aquatic macrophytes. These plants require special adaptations for living submerged in water, or at the water's surface. Aquatic plants can only grow in water or in soil that is...

 vegetation
Vegetation
Vegetation is a general term for the plant life of a region; it refers to the ground cover provided by plants. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic characteristics. It is broader...



Its numbers have declined by about one-third since the 1990s due to unsustainable water usage for agriculture
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...

, pollution
Pollution
Pollution is the introduction of contaminants into a natural environment that causes instability, disorder, harm or discomfort to the ecosystem i.e. physical systems or living organisms. Pollution can take the form of chemical substances or energy, such as noise, heat or light...

 and competition with introduced species
Introduced species
An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...

. Whether hybridisation with the more numerous L. bocagei also affects its numbers is not known. The two must have achieved reproductive isolation
Reproductive isolation
The mechanisms of reproductive isolation or hybridization barriers are a collection of mechanisms, behaviors and physiological processes that prevent the members of two different species that cross or mate from producing offspring, or which ensure that any offspring that may be produced is not...

 in the past to become as disting as they are, but dam
Dam
A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are...

ming and other construction have in recent times shifted the river's currents
Current (stream)
A current, in a river or stream, is the flow of water influenced by gravity as the water moves downhill to reduce its potential energy. The current varies spatially as well as temporally within the stream, dependent upon the flow volume of water, stream gradient, and channel geometrics...

 and changed microhabitat, so that these barbels will now meet at spawn
Spawn (biology)
Spawn refers to the eggs and sperm released or deposited, usually into water, by aquatic animals. As a verb, spawn refers to the process of releasing the eggs and sperm, also called spawning...

ing sites more often. Altogether however, damming will slow the river's flow to almost a standstill, creating conditions more favourable to the Iberian Barbel than to L. bocagei, and the hybridisation may actually be a sign of the rarer species becoming more plentiful.

In any case, the unsustainable extraction of for agriculture is the main threat of L. comizo. It is by no means as common as it was in past times, and classified as a Vulnerable
Vulnerable species
On 30 January 2010, the IUCN Red List of Threatened Species identified 9694 Vulnerable species, subspecies and varieties, stocks and sub-populations.-References:...

 by the IUCN. It is listed in Annex II of the European Union
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...

's Habitats Directive as a Species Requiring Designation of Special Conservation Areas, and in Annex V to allow for legal restrictions to its taking. It is also named as Protected Species in Appendix III of the Convention on the Conservation of European Wildlife and Natural Habitats
Convention on the Conservation of European Wildlife and Natural Habitats
The Bern Convention on the Conservation of European Wildlife and Natural Habitats 1979, also known as the Bern Convention , came into force on June 1, 1982....

.
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