Development of microsatellite markers for muskellunge (Esox masquinongy) and cross-species amplification in two other esocids

We report the development of seven polymorphic microsatellite loci in muskellunge ( Esoxmasquinongy ) using an unenriched subgenomic library. Polymorphic loci exhibited 2–11alleles with observed heterozygosities ranging from 0.190 to 0.917 ( n = 24). All seven lociamplified by their respective primer pairs resulted in monomorphic products in northernpike ( E. lucius ) whereas three loci amplified monomorphic products in grass pickerel( E. americanus americanus ); these results imply conservation of flanking sequence butloss of polymorphism between these closely related species. Only one of six microsatelliteprimers developed in a previous study in northern pike amplified polymorphic productsin muskellunge. Keywords : Esox , grass pickerel, microsatellite, muskellunge, northern pike Received 17 February 2003; revision received 14 May 2003; accepted 14 May 2003 The muskellunge ( Esox masquinongy ) is a large predatoryfish common to lakes and large rivers in northern USand Canada. Despite the important ecological role that themuskellunge plays as the apex predator in many fresh-water ecosystems and the value of the species to recre-ational fisheries there has been very little investigationof the genetic population structure of this species. In theonly published study of muskellunge genetic variationKoppleman & Philipp (1986) found significant variation atseveral allozyme markers between muskellunge fromwidespread localities within North America. The potentialfor genetic stock structure may be of particular importanceconsidering the widespread stocking of muskellungethroughout North America. Microsatellites have beenisolated for the northern pike (