The biological status of the commercially important polychaete Americonuphis reesei was analyzed in capture areas, during extraction and closed periods at Pacora and Tres Islas beaches, gulf of Montijo, Panama. Samples were collected for six months, three in the extraction period of 2015 and three in the closed season of 2016, during the lowest monthly syzygy tide, in three quadrants of 5 x 5 m, parallel to the waterline, captured with bicycle air pump, to analyze biometrics and calculate density. The height and weight in the extraction period were 1.06 m and 40.45 g, while in the closed season were 0.98 m and 29.0 g respectively. The density in the extraction period varied from 2.45 to 12.85 ind/m2 in Playa Pacora, and in the closed period from 0 to 0.05 ind/m2 in Playa Tres Islas.