Razor Shell

Razor Shell

Observation - Razor Shell - Global. Description: Need some help and guidance on this one. I always thought there was only one species of razor shell - but as usual I was wrong. Looking at the website of the Choncological Society, http://www.conchsoc.org and using an id guide http://www.nbn.org.uk/nbn_wi

Need some help and guidance on this one. I always thought there was only one species of razor shell - but as usual I was wrong. Looking at the website of the Choncological Society, http://www.conchsoc.org and using an id guide http://www.nbn.org.uk/nbn_wide/media/Documents/ID%20Resources/Shell-identification-February-2012-version-Ian-Wallace.pdf
I've decided I'm confused!
I think this may be E. siliqua because it looks straight to my eye. Overall length 17cm.
As a side point there were large numbers of razor shells along the strand line.