Genetic variability of Tehuelche scallop, Aequipecten tehuelchus, populations from the Patagonian coasts (Argentina)

LUCIANO REAL; NESTOR CIOCCO; NORMA JULIO; NOEMI C. GARDENAL

JOURNAL OF THE MARINE BIOLOGICAL ASSOCIATION OF THE UNITED KINGDOM

CAMBRIDGE UNIV PRESS

Lugar: Cambridge; Año: 2004 p. 235 - 238

0025-3154

Genetic variation was investigated in ¢ve subtidal locations from the north of San Mat|¤as Gulf (428230S) to the north of San Jorge Gulf (458020S). Fifteen loci were studied by means of vertical starch gel electrophoresis; ten loci were polymorphic. The percentages of polymorphic loci (P0.99 and P0.95 criteria) varied between 40% and 53.33% and between 33.33% and 46.67%, respectively. Expected mean heterozygosity per locus (He) ranged from 0.128 (Bajo Oliveira-El So¤tano) to 0.160 (PuertoMadryn); this range is similar to those observed for other scallop species. All the loci were in Hardy^Weinberg equilibrium. The estimated genetic distances among populations were signi¢cantly lower than those reported for comparisons between populations of di¡erent pectinid species, suggesting that the ¢ve populations studied belong to the same species (Aequipecten tehuelchus). The absence of exclusive ¢xed alleles also supported that assumption. The results obtained suggest: (i) assignment of species or subspecies status to some morphological variants of the shells, like the ?madrynensis? form is not supported; (ii) the commercially exploited Tehuelche scallop from San Mat|¤as and San Jose¤ Gulfs should be managed as distinct stocks.8230S) to the north of San Jorge Gulf (458020S). Fifteen loci were studied by means of vertical starch gel electrophoresis; ten loci were polymorphic. The percentages of polymorphic loci (P0.99 and P0.95 criteria) varied between 40% and 53.33% and between 33.33% and 46.67%, respectively. Expected mean heterozygosity per locus (He) ranged from 0.128 (Bajo Oliveira-El So¤tano) to 0.160 (PuertoMadryn); this range is similar to those observed for other scallop species. All the loci were in Hardy^Weinberg equilibrium. The estimated genetic distances among populations were signi¢cantly lower than those reported for comparisons between populations of di¡erent pectinid species, suggesting that the ¢ve populations studied belong to the same species (Aequipecten tehuelchus). The absence of exclusive ¢xed alleles also supported that assumption. The results obtained suggest: (i) assignment of species or subspecies status to some morphological variants of the shells, like the ?madrynensis? form is not supported; (ii) the commercially exploited Tehuelche scallop from San Mat|¤as and San Jose¤ Gulfs should be managed as distinct stocks.8020S). Fifteen loci were studied by means of vertical starch gel electrophoresis; ten loci were polymorphic. The percentages of polymorphic loci (P0.99 and P0.95 criteria) varied between 40% and 53.33% and between 33.33% and 46.67%, respectively. Expected mean heterozygosity per locus (He) ranged from 0.128 (Bajo Oliveira-El So¤tano) to 0.160 (PuertoMadryn); this range is similar to those observed for other scallop species. All the loci were in Hardy^Weinberg equilibrium. The estimated genetic distances among populations were signi¢cantly lower than those reported for comparisons between populations of di¡erent pectinid species, suggesting that the ¢ve populations studied belong to the same species (Aequipecten tehuelchus). The absence of exclusive ¢xed alleles also supported that assumption. The results obtained suggest: (i) assignment of species or subspecies status to some morphological variants of the shells, like the ?madrynensis? form is not supported; (ii) the commercially exploited Tehuelche scallop from San Mat|¤as and San Jose¤ Gulfs should be managed as distinct stocks.0.99 and P0.95 criteria) varied between 40% and 53.33% and between 33.33% and 46.67%, respectively. Expected mean heterozygosity per locus (He) ranged from 0.128 (Bajo Oliveira-El So¤tano) to 0.160 (PuertoMadryn); this range is similar to those observed for other scallop species. All the loci were in Hardy^Weinberg equilibrium. The estimated genetic distances among populations were signi¢cantly lower than those reported for comparisons between populations of di¡erent pectinid species, suggesting that the ¢ve populations studied belong to the same species (Aequipecten tehuelchus). The absence of exclusive ¢xed alleles also supported that assumption. The results obtained suggest: (i) assignment of species or subspecies status to some morphological variants of the shells, like the ?madrynensis? form is not supported; (ii) the commercially exploited Tehuelche scallop from San Mat|¤as and San Jose¤ Gulfs should be managed as distinct stocks.Aequipecten tehuelchus). The absence of exclusive ¢xed alleles also supported that assumption. The results obtained suggest: (i) assignment of species or subspecies status to some morphological variants of the shells, like the ?madrynensis? form is not supported; (ii) the commercially exploited Tehuelche scallop from San Mat|¤as and San Jose¤ Gulfs should be managed as distinct stocks.madrynensis? form is not supported; (ii) the commercially exploited Tehuelche scallop from San Mat|¤as and San Jose¤ Gulfs should be managed as distinct stocks.