Atrina rigida (Lightfoot, 1786)
Stiff pen shell
Atrina rigida
photo by Coltro, Marcus

Family:  Pinnidae (pen shells)
Max. size:  30 cm NG (male/unsexed)
Environment:  benthic; marine; depth range 0 - 27 m
Distribution:  Western Central Atlantic.
Diagnosis:  Diagnostic features: Shell large, fan-shaped, triangular. Surface sculpture of about 15 narrow radial ribs separated any larger interspaces; ribs bearing regularly spaced, fluted spines. Large muscle scar inside shell touches border of nacreous area. Hinge area straight, representing larger side of triangular shell outline. Byssus at pointed extremity anchors penshell into seagrass bottom. Gaping shorter side of triangular shell outline oriented upward. Colour: dark olive brown; mantle colour bright golden orange. Fisheries: Commercially exploited in and around Campeche, Mexico. Consumed locally in soups, marinated, or grilled (Ref. 271).
Biology: 
IUCN Red List Status: Not Evaluated (N.E.) Ref. 123251)
Threat to humans: 
Country info:   
 

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