Titre du document / Document title

Population genetics of the northern Pacific seastar Asterias amurensis (Echinodermata: Asteriidae) : allozyme differentiation among Japanese, Russian, and recently introduced Tasmanian populations

Auteur(s) / Author(s)

WARD R. D. ; ANDREW J. ;

Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)

CSIRO div. fisheries, Hobart Tasmania 7001, AUSTRALIE

Résumé / Abstract

The northern Pacific seastar Asterias amurensis Lütken was recently introduced to Tasmanian waters, possibly through ballast water discharged from ocean-going vessels. Three Tasmanian populations and seven native populations from Japan and eastern Russia were examined in 1994 for variation at 22 allozyme loci. There was significant spatial heterogeneity in gene frequencies among the native populations, especially for the locus APK^*, where G_ST was a very high 0.47. The Tasmanian populations could not be separated genetically from one another, suggesting they have a common origin from a single introduction. The average heterozygosity per locus of the Tasmanian populations (0.116 to 0.127, mean 0.123) was ∼30 to 40% less than that of the native populations (0.177 to 0.216, mean 0.192), suggesting that colonisation of Tasmanian waters was accompanied by a population-size bottleneck. The Tasmanian seastars were genetically more closely related to the two populations from central Japan (Suruga and Tokyo Bays) than to populations from Vladivostok, northern Japan (Yoichi, Nemuro and Mutsu Bays) or southern Japan (Ariake Sea). However, there were significant differences between the populations from Tasmania and central Japan, which may be attributable to founder effects or may mean that the true source of the Tasmanian introduction has yet to be identified.

Revue / Journal Title

Marine biology   ISSN 0025-3162   CODEN MBIOAJ 

Source / Source

1995, vol. 124, n^o1, pp. 99-109 (25 ref.)

Langue / Language

Anglais

Editeur / Publisher

Springer, Berlin, ALLEMAGNE  (1967) (Revue)

Mots-clés anglais / English Keywords

Population genetics ; Allozyme ; Gene frequency ; Genetic variability ; North Pacific ; Asterias amurensis ; Pacific Ocean ; Marine environment ; Asteroidea ; Echinodermata ; Invertebrata ;

Mots-clés français / French Keywords

Génétique population ; Allozyme ; Fréquence génique ; Variabilité génétique ; Océan Pacifique Nord ; Asterias amurensis ; Océan Pacifique ; Milieu marin ; Asteroidea ; Echinodermata ; Invertebrata ; Asteriidae ;

Mots-clés espagnols / Spanish Keywords

Genética población ; Aloenzima ; Frecuencia génica ; Variabilidad genética ; Océano Pacífico Norte ; Asterias amurensis ; Océano Pacífico ; Medio marino ; Asteroidea ; Echinodermata ; Invertebrata ;

Localisation / Location

INIST-CNRS, Cote INIST : 8506, 35400005904389.0120