ingles, Fartet Lebias (=Aphanius) ibera

Common and vernacular names: fartet (es), fartonet (val), peixet de xequiol (cat).

Description: Small fish with oblong body and rounded fins. Mouth directed upwards with maxillary teeth with three apex and disposed in only one row. Relatively big scales. Sexual dimorphism quite apparent, males are coloured with several blue and silver vertical bars and patterns in the fins, mainly the anal, which is crossed by wide dark vertical lines. Females are generally brown-greenish with several irregular dark spots all over their body, their fins are transparent without any marks. Some populations have short vertical lines instead of spots (Murcia).


Lebias ibera, male from Albuixec (Valencia), which is today a desiccated marsh. © Salvador Peiró (CAE).	Fartet female, Lebias ibera. © Salvador Peiró (CAE).

Size: Very rarely they are over five centimetres (2´´) in total length, usually being females bigger than males of the same age.

Habitat: Very different. Pools, lakes, littoral lagoons, irrigation channels, marshes. Almost always in quiet or slow flowing water. It can endure a wide range of temperature and salinity, from very soft water till water saltier than the sea (See Bibliography: Aparicio, Oltra, Romero, Sanz...).

Geographic distribution: It lived originally along the Mediterranean coastal region of the Iberian Peninsula; there are even some appointments (maybe a confusion with Aphanius fasciatus) in Coursan, south of France (Arnoult 1957, recopilated by Leboulanger 1997), the populations from the Southern Atlantic region in the low Guadalquivir basin has recently (2.002) being described as a new species: Aphanius baeticus. A similar form is found in Northern Africa (Pellegrin 1921, Villwock 1970), although it’s taxonomic status is not clear (Villwock and Scholl 1982). Nowadays there are a dozen of relict isolated populations in this distribution range in the Iberian Peninsula.

Theoretical geographic distribution of the Fartet (Lebias ibera) in the Iberian Penisula.

Habits: It usually swims in small groups next to the surface among the aquatic vegetation, where it is not easily detected. During the mating season, adult males defend small territories by way of ritual combats against other males, courting the females that swimm into these territories.

Feeding: Small omnivorous fish, its nourishment is based in small invertebrates (insect larvae, crustaceans ...) and vegetal materials, mainly algae.

Reproduction: It generally happens between the months of April and September (both inclusive). During this time, the territorial males develop a striking nuptial courting, consisting of lateral exhibitions and circular movements around the female. If she is ready and willing, they both swim towards an adequate substrate such as thin leaves of aquatic plants, bunches of filamentous algae, etc., where the eggs are laid and fertilised. Eggs are about 1 mm in diameter and are transparent in the beginning and very adhesive by way of filaments, they are laid one by one or in small groups. The total number for a single female in one breeding season may be about one thousand, but in several times. Hatching happens about eight days later (at the usual temperatures at this time of year). The growth rate is high in the beginning and they soon become mature, individuals that are born in April may be breeding in June, before being three months old.

Other comments: Nowadays, surviving populations are being displaced towards water bodies with a higher salinity, because of the competitive pressure of Gambusia holbrooki, which was introduced in Spain in the middle 1920´s to fight against mosquito larvae that transmitted paludism.

Interest: It is an endemic species of the Iberian Peninsula which is in extreme danger of extinction. Some of the populations are very different from others (at least from a genetic point of view). It is the most appreciated Iberian species by aquarium hobbyists therefore it is quoted in many books, papers, etc, published in different European countries.

Menaces: As for most continental fish, the main dangers come from human activities. In this particular case, destruction of habitats (waterland desiccation, case hardening of irrigation channels and other physical alterations), aquatic pollution (coming from industries, urban wastes, or agricultural products), and the introduction of competitive species such as Gambusia holbrooki and Fundulus heteroclitus, or predators like Black-bass or Sunfish, are the factors that most affect Fartets.

Protection and present status: Bern convention: Annex II (Mediterranean origin). Directive 92/43/CE 21st May 1992, about conservation of natural habitats and wild flora and fauna: Annex II (species of Communitary Interest whose conservation needs the designation of special zones). National Catalogue of Endangered Species (R.D. 439/1990. BOE 5/4/90) Annex I "in danger of extinction". Law 7/1995 (Comunidad Autónoma de Murcia): "In danger of extinction". Llei 3/1988 (Comunidad autónoma de Cataluña): "Protected species". Red List of Spanish Vertebrates (ICONA, 1.986): "in danger of extinction". UICN DD (data defficient)