Brown rangia

Rangia flexuosa

Family Mactridae - rangias

Distinguishing
Characteristics
Bivalve (2 shells); shell heavy, somewhat triangular; anterior end broadly rounded; posterior end angular, pointed; distinct ridge from beak to posterior end; color whitish but covered with a blackish to brown exterior coating (periostracum); shell with concentric ridges and grooves; beak near rounded anterior end, twisted anteriorly; small gap between beaks; interior white; pallial sinus minute or absent; enlarged tooth near beak in both shells; inside posterior margin with short ridge (lateral tooth), does not reach posterior end.
Similar Species
Similar to the Atlantic rangia, but the Atlantic rangia has a rounded posterior end, a larger pallial sinus ( small to no sinus in the brown rangia) and a longer ridge (lateral tooth) on posterior margin. May be confused with the southern or Texas quahog, but the quahogs have no gap between its beaks and has a short, rounded depression (lunule) just anterior to both beaks (no lunule in rangia)..
Habitat
Bays, low salinities, freshwater
Maximum Size
7.5 cm (3 in)
Other Common Names
Previous Scientific Names
Rangianella flexuosa
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