I am slightly confused by the classification of extinct for this species. I've been having trouble finding sources regarding the population at Pyramid Lake. There were lots of bleached shells along a little stretch of the beach. I also found 3-4 shells that were not bleached and are dark/black colored (see photos 2 & 4). Does that mean it's a newer shell? I don't know what the bleaching process is like for these shells. The sources I'm finding state "Only ever known from fossils and one live population in Nevada. Reported occurrences from Oregon refer to another species, P. ARCHIMEDIS. Recent investigators have failed to find any living individuals.". Information I recieved from the Nevada Natural Heritage Program states that, "The shells usually bleach in just a couple of years when they're on the surface and the last time one was collected alive was 1947." The Nevada Natural Heritage Program will be searching for live specimens at this location soon! Hopefully they can find some!

http://explorer.natureserve.org/servlet/NatureServe?searchName=Pyrgulopsis+nevadensis

https://en.wikipedia.org/wiki/Corded_purg