U.S. Fish & Wildlife Service Scaleshell Mussel Oklahoma Ecological Service Field Office Scaleshell mussel Leptodea leptodon Description The scaleshell mussel occurred historically across much of the eastern U.S., but recently is known only from scattered populations in Arkansas, Missouri, Oklahoma, Nebraska, and South Dakota. In Oklahoma, the species survives in the Kiamichi River in southeastern Oklahoma, and historical records exist from the Little and Mountain Fork rivers, also in southeastern Oklahoma. Its thin, elongated shell reaches a maximum length of about 4.75 inches. Males and females have differently shaped shells, most apparent in a broad, ruffled Scaleshell mussel. © Dr. M.C. Barnhart extension of the females’ posterior end. The outer shell layer is yellowish-brown Conservation to protect water quality, restore and with fine green rays. It is distinguished The scaleshell mussel was federally listed protect natural watershed conditions, from other freshwater mussel species by as an endangered species on October 9, conserve instream flows, and prevent the additional distinctive details of its shell. 2001. This species has experienced severe spread of aquatic invasive species. Learn losses in range and abundance due to more about the scaleshell mussel, the Distribution human degradation of its habitat. Specific threats to its existence, and its identified The scaleshell mussel lives in medium- factors involved in this degradation conservation needs by consulting the sized to large rivers with stable channels include construction and operation of species’ recovery plan. and good water quality. The species large impoundments, and water quality inhabits sand and gravel stream bottoms degradation from point sources and References where individuals bury themselves, with nonpoint sources of pollution. Many of U.S. Fish and Wildlife Service. 2010. only the edge of their partially-opened these factors are expected to continue Scaleshell Mussel Recovery Plan. Fort shells exposed. and may increase, posing future threats Snelling, Minnesota. to the scaleshell. Additional potential Life History threats include impacts from invasive U.S. Fish and Wildlife Service. 2011. Adults feed by filtering algae, other aquatic species such as the introduced Scaleshell Mussel (Leptodea leptodon) protoctists, microscopic animals, bacteria, zebra mussel (Dreissena polymorpha), 5-year Review: Summary and and detritus from their surroundings. and extreme conditions associated with Evaluation. Columbia, Missouri. As with most freshwater mussels, the human-caused climate change. life cycle includes sexual reproduction For Further Information and a required parasitic stage. During What You Can Do To Help U.S. Fish and Wildlife Service spawning, males release sperm into If you have property within a watershed Oklahoma the water column, some of which are inhabited by the scaleshell mussel, Ecological Services Field Office taken into females of the species, which maintain an ample buffer of natural 9014 East 21st Street carry eggs in their gills. The resulting vegetation alongside any stream Tulsa, OK 74129 larvae (known as glochidia) are released channels. Treat eroding roads, slopes, 918/581-7458 from the females into the water column and other sources contributing sediments and must attach to a suitable fish to streams. Reduce or eliminate use of host to continue development. Once lawn-care/agricultural chemicals, and August 2011 metamorphosis is complete, juvenile install fencing to prevent livestock from mussels drop off the fish host and entering streams. Take other steps continue life in the stream bottom. Known fish hosts for this species include the freshwater drum (Aplodinotus grunniens)..