Gulf of Mexico, Mexico, Campeche, Isla Del Carmen, Boca del Puerto Real, San Julian, at the entrance of Laguna de Términos (geocoordinates not provided, estimated with gazetteer to be approximately lat. 18.754º, long. -91.511º); in very shallow waters (0.1-0.5 m), associated with Rhizophora mangle mangrove vegetation, in soft sediments (about 2/3 mud and 1/3 sand)