Systematic status of two oyster populations of the genus Tiostrea from New Zealand and Chile

A systematic examination of Tiostrea chilensis endemic to the Pacific coast of South America and of T. lutaria endemic to new Zealand was conducted using protein-gel electrophoresis. Also, ecological and life-history traits were compared between these two documented species. Our study revealed that although three different ecomorphs could be distinguished from various environmental and ecological conditions, the life-history traits between the two species were remarkably similar. Estimates were made of levels of genetic variation and similary based on 29 structural loci among individuals from each documented species. The percentage of loci polymorphic was estimated at 17.2 and 17.6, while the percentage of loci heterozygous was 2.1 and 6.7 for T. chilensis and T. lutaria, respectively. The genetic similarity between the two species was computed as 0.991, where 1.0 indicates no genetic difference among structural loci. The overwhelming evidence of this study indicates that T. chilensis and T. lutaria are different geographical populations of one species and by priority this species should be T. chilensis.