Freshwater pearl mussel Freshwater pearl mussel The freshwater pearl mussel ("Margaritifera margaritifera") is an endangered species of freshwater mussel, an aquatic bivalve mollusc in the family Margaritiferidae. Although the name "freshwater pearl mussel" is often used for this species, other freshwater mussel species can also create pearls and some can also be used as a source of mother of pearl. In fact, most cultured pearls today come from "Hyriopsis" species in Asia, or "Amblema" species in North America, both members of the related family Unionidae; pearls are also found within species in the genus "Unio". The interior of the shell of "Margaritifera margaritifera"
Hymn of the Pearl has been preserved and especially treasured in Manichaeism - a version of it appears as part of a north-African Manichaean Psalm book is written in Coptic, called the Psalms of Thomas. The Hymn of the Pearl has also been admired by Orthodox Christian thinkers and members of the Church of Jesus Christ of Latter-Day Saints (Mormons). Please note that wikisource contains the . The "Hymn of the Pearl" is read as part of the narration in Terrence Malick's 2015 film "Knight of Cups". The film deals with themes of pain, loss of direction and transcendence, which are part of the