found: Work cat.: COSEWIC assessment and status report on the Mapleleaf, Quadrula quadrula, Great Lakes - Upper St. Lawrence population, Saskatchewan - Nelson Rivers population, in Canada, 2016.
found: ITIS website, November 15, 2017(Quadrula quadrula, Common name - Mapleleaf; Genus - Quadrula, Family - Unionidae, Order - Unionoida, Class - Bivalvia, Phylum - Mollusca, Kingdom - Animalia; Synonyms - Obliquaria quadrula, Unio rugosus, Unio lacrymosus, Unio asperrimus, Unio lunulatus)
found: NatureServe Explorer website, November 20, 2017(Quadrula quadrula, Mapleleaf Mussel; Genus - Quadrula, Family - Unionidae, Order - Unionoida, Class - Bivalvia, Phylum - Mollusca, Kingdom - Animalia)
found: IUCN Red List of Threatened Species website, November 20, 2017(Quadrula quadrula; Family - Unionidae, Order - Unionoida, Class - Bivalvia, Phylum - Mollusca, Kingdom - Animalia)
found: Encyclopedia of Life website, January 8, 2018(Quadrula quadrula; Mapleleaf; distribution: The mapleleaf is found in Mississippi River drainage north to the Red River of the North and Nelson River. It is also found in the Great Lakes, south to the Gulf drainages in the Alabama river and some streams of eastern and central Texas)