Medionidus penicillatus NatureServe Explorer Species Reports — NatureServe Explorer is a source for authoritative conservation information on more than 50,000 plants, animals and ecological communtities of the U.S and Canada. NatureServe Explorer provides in-depth information on rare and endangered species, but includes common plants and animals too. NatureServe Explorer is a product of NatureServe in collaboration with the Natural Heritage Network. Medionidus penicillatus, the gulf moccasinshell, is a rare species of freshwater mussel in the family Unionidae, the river mussels. This aquatic bivalve mollusk is native to Alabama, Florida, and Georgia in the United States, where it is in decline and has been extirpated from most of the rivers it once inhabited. It is a federally listed endangered species of the United States.
ITIS Reports — ITIS (the Integrated Taxonomic Information System) is a source for authoritative taxonomic information on plants, animals, fungi, and microbes of North America and the world.
FWS Digital Media Library — The U.S. Fish and Wildlife Service’s National Digital Library is a searchable collection of selected images, historical artifacts, audio clips, publications, and video. The Medionidus penicillatus (Gulf moccasinshell) is a small mussel that reaches a length of about 2.2 in (55 mm), is elongate-elliptical or rhomboidal and fairly inflated, and has relatively thin valves. The ventral margin is nearly straight or slightly rounded.