Atlantic rangia

Rangia cuneata

Family Mactridae - rangias

Distinguishing
Characteristics
Bivalve (2 shells); shell heavy, somewhat triangular; anterior end broadly rounded; posterior end rounded but more angular; 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 small; enlarge tooth near beak in both shells; posterior inner margin with long ridge (lateral tooth) from beak to near posterior end.
Similar Species
Similar to the brown rangia, but the brown rangia has an angular pointed posterior end, very small or no pallial sinus and a shorter 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 have a short, rounded depression (lunule area) just anterior to both beaks (no lunule in rangia).
Habitat
Bays, low salinities, freshwater
Maximum Size
9.4 cm (3 3/4 in)
Other Common Names
Previous Scientific Names
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