Genetic divergence in Greek populations of the genus Leuciscus and its evolutionary and biogeographical implications

Abstract

In 23 populations of Greek Leuciscus (Squalius), the percentage of polymorphic allozyme loci ranged between 0·034 and 0·379 (P=0·19) and expected heterozygosity was 0·011–0·166 (He=0·067). Current taxonomy is confusing and does not correspond to genetic data that support the presence in Greece of at least seven different species: L. cephalus, L. peloponnensis, L. prespensis, L. moreoticus, L. borysthenicus, L. keadicus and Leuciscus sp. from Euboea Island. The maximum Nei modified genetic distance was found among L. keadicus and the rest of subgenus Squalius populations D* Nei=0·446–0·705). Accepting the molecular clock hypothesis, speciation for the genus Leuciscus in Greece must have occurred during the Cenozoic period (between the Middle Miocene and the Later Pliocene). The two main biogeographical events causing speciation on mainland Greece were the Uplift of the Pindic cordillera and the isolation of the southern part of Peloponnesus. The faunistic composition of the lakes studied, in which new taxa are reconsidered, suggests the same faunistic origin in the Early Pliocene for Lakes Prespa and Stymphalia and a younger one in the Late Pliocene for Lake Trichonis. Euboea Island was not a zoogeographical unit during the Cenozoic. The isolation of all the freshwater fish fauna of Euboea has occurred since the Pliocene. The biogeographical model proposed here differs from classical hypotheses in considering of lesser importance the dispersion of L. cephalus on the Greek mainland during the Neogene and Quaternary.

Phylogenetic Relationships of Greek Cyprinidae: Molecular Evidence for at Least Two Origins of the Greek Cyprinid Fauna

“…Recently, allozyme markers have been used to study phylogenetic relationships of several Greek cyprinids at the genus level (Karakousis et al, 1995;Tsigenopoulos and Karakousis, 1996;Gollman et al, 1997;Doadrio and Carmona, 1998;Imsiridou et al, 1998). Yet, phylogenetic relationships among Greek cyprinid species are still poorly understood, and the taxonomic validity of genera such as Tropidophoxinellus or Pachychilon is under debate (Kottelat, 1997).…”

A new species of the genus <i>Squalius</i> Bonaparte, 1837 (Actinopterygii, Cyprinidae) from the Tagus River Basin (Central Spain)

“…This genus includes approximately 15 species (Kottelat 1997;Doadrio & Carmona 1998) distributed along the Mediterranean basin; two species are widely reported in Central and North Europe (Sanjur et al, 2003).…”

The freshwater ichthyofauna of Greece - an update based on a hydrographic basin survey

“…Species of some genera (e.g. Squalius, Scardinius and Barbus) show deep genetic divergence from their counterparts in the Balkans and the rest of Europe and often have a basal or almost basal position in phylogenetic reconstructions (DOADRIO & CARMONA, 1998;KETMAIER et al, Medit. Mar.…”

“…peloponnensis although we do give the specific three taxa proposed by K&F 2007 in the specific recorded basins. Despite considerable amount of genetic work (IMSIRIDOU et al, 1997(IMSIRIDOU et al, , 1998(IMSIRIDOU et al, , 2000DOADRIO & CARMONA, 1998SANJUR et al, 2003;ZARDOYA et al, 1999;DURAND et al, 1999bDURAND et al, , 2000, further taxonomic research involving populations from northern and south-western Peloponnese as well as from the Epirus rivers is needed to resolve the problem of Squalius species distinction in the Ionian basins. 20 Squalius moreoticus described as Leuciscus cephalus moreoticus by STEPHANIDIS (1939) was originally considered as being confined to Lake Stymphalia.…”