Molecular phylogeny of Acipenserinae and black caviar species identification.

The first phylogenetic tree for the Acipenserinae based on the combined seq uence data for fragments of three mitochondrial genes, the cytochrome b (65 0 bp) gene, 12S (150 bp) and 16S (350 bp) rRNA genes is described. Three ge neral conclusions are inferred from the tree: 1) Scaphirhynchus albus is th e sister-species of an Acipenser and Huso species: 2) The two species of Hu so are embedded within the genus Acipenser. Therefore, the genus Huso is no t a separate taxonomic unit: and 3) There are three main clades within Acip enser: (a) A. sturio-A. oxyrinchus (b) A. schrenckii-A. transmontanus. and (c) all Ponto-Caspian species plus A. dabryanus and A. brevirostrum. A meth od based on the identification of diagnostic nucleotide positions in the cy tochrome b gene was developed and used to survey the United States and Euro pean caviar markets. The survey of 95 lots of caviar obtained at the Americ an market suggests that in December 1995 and April 1996 I 7% of the designa tions made by caviar suppliers were mislabeled with respect to species iden tification. In December of 1996, this figure jumped to 32%. The main commer cially harvested species (Huso huso, A. stellatus, A. grueldenstaedtii, 4. schrenckii, and H dauricus), as well as A. nudiventris, A. persicus, and A. baerii are threatened due to the increased demand of the international cav iar market.