I am working on a monographic book on the marine bivalves from Peru and Chile (6-44°S). It has been difficult to find specimens outside of those two regions. Does anyone know of collections from this region in the USA?
In northern Chile, I recommend you visit the Museo del Mar, from the University of Arturo Prat, located in Iquique city. There exist an adequate collection of Bivalves. In Santiago you can visit the Museo de Historia Natural (http://www.mnhn.cl/Vistas_Publicas/publicContenido/contenidoPublicDetalle.aspx?folio=4942). In latter museum you can find an extensive vouchers of bivalves from Chilean coast.
I don’t know about collection in the US. But the Museo de Zoologia de la Universidad de Concepción, Concepción has a good holding of marine bivalves. There should be several other minor collections in Chile. Certainly, many colleagues working at Chile (e.g., Javier Sellanes, Sven Nielsen) study these animals, and contacting would be a of much help.