''Squalius carolitertii'' is a species of fresh-water fish in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Cyprinidae. It is found in

Portugal Portugal, officially the Portuguese Republic ( pt, República Portuguesa, links=yes ), is a country whose mainland is located on the Iberian Peninsula of Southwestern Europe, and whose territory also includes the Atlantic archipelagos of ...

and

Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = ''Plus ultra'' (Latin)(English: "Further Beyond") , national_anthem = (English: "Royal March") , i ...

, and known there as the ''bordallo, escalo'' or ''gallego''. Its natural

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

s are

river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of w ...

s and intermittent rivers. It is not considered threatened by the IUCN.

Distribution

The Northern Iberian chub, ''Squalius carolitertii'' is a small endemic cyprinid inhabiting the rivers of the Iberian Peninsula across a large area, including the Douro, Mondego, Lima, Minho, and Lérez basins. Recently several researchers have reported this species for the first time from the upper reaches of the Alberche River (a tributary of the

Tagus basin The Tagus Basin is the drainage basin of the Tagus River, which flows through the west of the Iberian Peninsula and empties into Lisbon. It covers an area of 78,467 km2, which is distributed 66% (55,645 km2) on Spanish territory and 34% on Po ...

in central Spain) and in the Oitavén River (a tributary of the Verdugo River in northwestern Spain).

Diet

''S. carolitertii'' is an omnivorous fish feeding predominantly on aquatic invertebrates, being nymphs of ''

Baetis ''Baetis'' is a genus of mayflies of the family Baetidae, known as the blue-winged olive to anglers. There are at least 150 described species in ''Baetis''. They are distributed worldwide, with the most variety in North America and norther ...

'' spp. the most abundant prey, although detritus is an important food item. Moreover, in ''S. carolitertii'', as in many other fish species, there is normally a change in the diet composition during the life of the fish, and these age-related diet shifts occur at three different levels: (1) frequency of occurrence of detritus decreases with fish age; (2) prey selection varies with fish age; and (3) mean prey size increases as fish size increased.

Distribution

Diet

References

Further reading