The covering of the eggs in Russian sturgeon Acipenser gueldenstaedtii consists of three envelopes (the vitelline envelope, chorion and extrachorion) and is equipped with multiple micropyles. The most proximal to the oocyte is the vitelline envelope that consists of four layers of filamentous and trabecular material. The structural components of this envelope are synthesized by the oocyte (prim...

Sequencing analysis was used to characterize a mtDNA D-Ioop amplicon of 838 bp. Four pallid sturgeons, Scaphirhynchus albus, and four shovelnose sturgeons, S. platorynchus, from four states (Illinois, Louisiana, Montana, North Dakota) were used for this analysis. DNA sequencing ofthe nine fish revealed eleven polymorphic sites and six distinct haplotypes. No fixed nucleotide substitutions were ...

Significant intraindividual variation in the sequence of the 18S rRNA gene is unusual in animal genomes. In a previous study, multiple 18S rRNA gene sequences were observed within individuals of eight species of sturgeon from North America but not in the North American paddlefish, Polyodon spathula, in two species of Polypterus (Polypterus delhezi and Polypterus senegalus), in other primitive f...