1. Marine Gene Probe Laboratory; Biology Department; Dalhousie University; Halifax Nova Scotia B3H 4R2 Canada
2. Biology Department; Dalhousie University; Halifax Nova Scotia B3H 4R2 Canada
3. Institute of Hydrobiology; Fish Ecology Unit; Biology Centre of the Academy of Sciences of the Czech Republic; Na Sádkách 7 České Budějovice 370 05 Czech Republic