Synonymy in the family Margaritifera (Bivalvia: Unionidae)

Ontogeny of juvenile freshwater pearl mussels, Margaritifera margaritifera (Bivalvia: Margaritiferidae)

The gills of juvenile freshwater bivalves undergo a complex morphogenesis that may correlate with changes in feeding ecology, but ontogenic studies on juvenile mussels are rare. Scanning electron microscopy was used to examine the ultrastructure and ontogeny of 117 juvenile freshwater pearl mussels (Margaritifera margaritifera) ranging in age from 1-44 months and length from 0.49-8.90 mm. Three...

Population structure and mantle display polymorphisms in the wavy-rayed lampmussel, Lampsilis fasciola (Bivalvia: Unionidae)

Genotypes from 10 polymorphic DNA microsatellite loci were used to make assessments of population structure, measurements of gene flow, and attempts to genetically segregate polymorphic host fish-attracting mantle displays for the wavy-rayed lampmussel, Lampsilis fasciola Rafinesque, 1820 — an endangered species in Canada. Specimens were collected from seven localities — six in the Great Lakes ...

Long-Term Decline in Freshwater Mussels (Bivalvia: Unionidae) of the Western Basin of Lake Erie

Long-term trends in the abundance of unionids in the western basin of Lake Erie were examined from data collected at 17 stations in 1961, 1972, and 1982. The mean number of unionids at these stations declined over this time period, decreasing from 10 m~2 in 1961, to 6 m~2 in 1972, down to 4 m~2 in 1982. This decline in abundance was reflected in the decrease in the number of stations where muss...

Geometrical and crystallographic constraints determine the self-organization of shell microstructures in Unionidae (Bivalvia: Mollusca).

Unionid shells are characterized by an outer aragonitic prismatic layer and an inner nacreous layer. The prisms of the outer shell layer are composed of single-crystal fibres radiating from spheruliths. During prism development, fibres progressively recline to the growth front. There is competition between prisms, leading to the selection of bigger, evenly sized prisms. A new model explains thi...

The mechanism of blood circulation in Anodonta anatina (L.) (Bivalvia, Unionidae).