Atlantic rangia 



Rangia cuneata 

 Adult 



2 cm 



(from Fischer 1978) 



Common Name: Atlantic rangia 



Scientific Name: Rangia cuneata 



Other Common Names: common rangia (Nelson et 



al. 1992); marsh clam (Burdon 1978); brackish water 



clam, road clam, wedge clam (LaSalle and de la Cruz 



1 985). 



Classification (Turgeon et al. 1988) 



Phylum: Mollusca 



Class: Bivalvia 



Order: Veneroida 



Family: Mactridae 



Value 



Commercial : The Atlantic rangia has been utilized for 

 several thousand years along the Gulf coast, begin- 

 ning with the Native Americans who made this clam a 

 part of their diet (Tarver 1 972, Tarver and Dugas 1 973, 

 LaSalle and de la Cruz 1 985). The commercial value 

 of this clam in now mainly in the use of its shell (both 

 fresh and fossil) in the manufacture of cement, glass, 

 chemicals, chicken and cattle feed, wallboard and 

 other building products, agricultural lime, road con- 

 struction and as fill in nearshore oil exploration (Tarver 

 and Dugas 1973, Arndt 1976, Fischer 1978). Rangia 

 shell is also used as substrate to enhance oyster 

 settlement in Florida and Louisiana (MacKenzie 1 996). 

 Rangia are sometimes used for blue crab bait and 

 some human consumption (Godcharles and Jaap 1 973, 

 LaSalle and de la Cruz 1985). Preparations include 

 chopped clam dishes, chowders, soups, and either raw 

 on the half shell, or steamed with rice dishes (Fischer 

 1978). It has also been canned occasionally for food 

 products (Pf itzenmeyer and Drobeck 1 964, Tarver and 

 Dugas 1973). Hand-collected rangia are sometimes 

 brought to cannery processors and added to hard clam 

 catches (Fischer 1978). 



Recreational : Recreational harvest of Atlantic rangia is 

 not significant in Gulf of Mexico estuaries. 



Indicator of Environmental Stress The Atlantic rangia 

 filter feeds on detritus, and is therefore susceptible to 

 the accumulation of pollutants from the particles on 

 which they feed. Because of this, they are commonly 

 used for tests of toxicity and bioaccumulation of petro- 

 leum products and by-products (Neff et al. 1976, Mo- 

 rales-Alamo and Haven 1982, Ferrario et al. 1985, 

 Jovanovich and Marion 1985, Bender et al. 1986), 

 organochlorine insecticides (Lunsford and Blem 1 982), 

 dioxins and furans from pulp mill effluent (Harrel and 

 McConnell 1 995), and heavy metals (Olson and Harrel 

 1973, Lytle and Lytle 1982, McConnell and Harrel 

 1995). They have been used in the past to monitor 

 radionuclides from radioactive debris resulting from 

 atmospheric testing of nuclear weapons (Wolfe 1967, 

 Wolfe and Schelske 1969). 



Ecological : The Atlantic rangia is an important compo- 

 nent of estuarine ecosystems, and can account for a 

 large portion of the benthic biomass in estuaries (Cain 

 1975, LaSalle and de la Cruz 1985). This species is 

 linked to primary producers and secondary consumers 

 in estuarine areas, because they convert detritus and 

 phytoplankton into biomass which can be utilized by 

 many fishes, birds, and crustaceans (Tenore et al. 

 1968, Hopkins and Andrews 1970, Cain 1975, Olsen 

 1976a, LaSalle and de la Cruz 1985). 



Range 



Overall : The Atlantic rangia occurs along the U.S. 

 Atlantic coast and in the Gulf of Mexico. Although there 

 is an extensive range for this species in the fossil 

 record, the present day range is more limited. Along 



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