Genetic differentiation between populations of Pomatoschistus minutus from the Bristol Channel and the Adriatic

Abstract

Samples from two populations of the gobiid fish species Pomatoschistus minutus (Pallas) were compared electrophoretically over 31 protein loci. The population from the Lagoon of Venice was shown to possess an extra LDH staining region, not present in P. minutus from Wales or any other congeneric population. ]'he manifestation of this additional 1,DH band is strongly suggestive of a distinct genetic locus. ]he two populations have a relatively low overall 1 value even if this disparity in LDH is neglected. This is largely a re'sult of virtually complete differentiation at two other Ldh loci. It is suggested that the large contribution by 3 out of the 4 Ldh loci to population differentiation, may indicate a specific adaptive response by the Venetian population to the unusual conditions of its habitat.

Allozyme variation and genetic divergence in the sand goby, Pomatoschistus minutus (Teleostei: Gobiidae)

“…Allele LDH-C*100 was not recorded in the Venetian sample but is the most common allele in all other samples (CAGE). Referring to Wallis & Beardmore (1983), we found no indications of a fourth locus, the so-called 'LDH-0*' in the Venetian sample.…”

“…The distinctness of the Venetian Pomatoschistus minutus at LDH-A* has been reported by Wallis & Beardmore (1983). They noticed that the distinct allele for P. minutus in the Venice lagoon at LDH-A* showed the same electrophoretic mobility as in the related estuarine species P. microps and suggested this distinct allele being an adaptive response to environmental pressures in a variable, enclosed environment.…”

“…Wallis & Beardmore (1984) carried out an extensive allozyme survey of the genus Pomatoschistus but only to con¢rm the systematic relationships between the species. They reported, however, clear-cut allozymatic di¡erences between P. minutus from the lagoon of Venice and the Atlantic Ocean (Wallis & Beardmore, 1983), which were con¢rmed by Stefanni et al (1996).…”

Quaternary climatic cycles promoted (re)colonization and diversification events in Adriatic sand gobies

“…A dichotomy between populations of P. minutus was already proposed in the early 1980s (Wallis & Beardmore, 1983) and subsequently repeatedly underlined (Boissin et al, 2011; Gysels et al, 2004; Huyse et al, 2004; Stefanni & Thorley, 2003). The Venice lineage is regarded as a separate Evolutionarily Significant Unit (sensu Moritz, 1994) by Stefanni and Thorley (2003) and as a cryptic species of Pomatoschistus by Gysels et al (2004).…”