On June 21, 2007, the crayfish (also known as crawfish and crawdad) became the official state invertebrate. Crayfish are an important food source for Missouri fishes. Missouri supports more than 30 species of crayfish (including seven species that occur nowhere else in the world). Crayfish are found in every county of the state and contribute to our unique biodiversity and conservation heritage. The nomination of crayfish for state invertebrate came from Mrs. Janna Elfrink's elementary school class in Reeds Spring, Missouri. (RSMo 10.125)
Crayfish, also known as crawfish, crawdads, freshwater lobsters, or mudbugs, are freshwater crustaceans resembling small lobsters, to which they are related; taxonomically, they are members of the superfamilies Astacoidea and Parastacoidea. They breathe through feather-like gills and are found in bodies of water. Some species are found in brooks and streams where there is fresh water running, while others thrive in swamps, ditches, and rice paddies. Most crayfish cannot tolerate polluted water, although some species such as the invasive Procambarus clarkii are hardier. Crayfish feed on living and dead animals and plants
The name "crayfish" comes from the Old French word escrevisse (Modern French ecrevisse). The word has been modified to "crayfish"
by association with "fish" (folk etymology). The largely American variant "crawfish" is similarly derived.
Some kinds of crayfish are known locally as lobsters, crawdads, mudbugs, and yabbies. In the Eastern United States, "crayfish" is more common
in the north, while "crawdad" is heard more in central and southwestern regions, and "crawfish" further south, although there are
considerable overlaps.
The study of crayfish is called astacology.
The law designating the crayfish as the official Missouri state invertebrate is found in the Missouri Revised Statutes, Title 2, Chapter 10, Section 10.125
Chapter 10
State Emblems
Section 10.125
August 28, 2013
Crayfish, official state invertebrate.
10.125. The crayfish, also called crawfish and crawdad, is selected for, and shall be known as, the official invertebrate of the state of Missouri.
(L. 2007 H.B. 351)
Taxonomic Hierarchy: Crayfish
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Crustacea
Class: Malacostraca
Order: Decapoda
Suborder: Pleocyemata
Infraorder: Astacidea
Superfamily: Astacoidea - Latreille, 1802 and Parastacoidea - Huxley, 1879