What is Razor shell?
{{Taxobox | name = ''Razor shell'' | image = Ensiskils.jpg | image_caption = ''Ensis arcuatis'' | image_width = 250px | regnum = [[Animal]]ia | phylum = [[Mollusca]] | classis = [[Bivalvia]] | ordo = [[Veneroida]] | familia = [[Pharidae]] | genus = '''''Ensis''''' | species = '''''E. arcuatus''''' | binomial = ''Ensis arcuatus'' | binomial_authority = ([[John Gwyn Jeffreys|Jeffreys]], 1865)&nbsp;<ref>{{cite web |author=S. Gofas |year=2010 |title=''Ensis arcuatus'' (Jeffreys, 1865) |editor=P. Bouchet, S. Gofas & G. Rosenberg |work=World Marine Mollusca database |publisher=World Register of Marine Species |url=http://www.marinespecies.org/aphia.php?p=taxdetails&id=140731 |accessdate=August 11, 2010}}</ref> }} [[File:Solen marginatus2.jpg|thumb|230px|right|''Solen marginatus'']] '''Razor shells''', also called '''razor clams''', are [[Bivalvia|bivalve]]s with the shape of an old-fashioned cut-throat [[razor]]. They use their [[shell (zoology)|shells]] to work into the sand and hide beneath the surface. '''''Ensis''''', of the family Pharidae, is found on sandy beaches in [[Northern Europe]] and [[Eastern Canada]], such as [[Prince Edward Island]]. ''Ensis arcuatus'' prefers coarser sand than its relatives ''E. ensis'' and ''E. siliqua''. There is also another family of razor shells, the Solenidae. Some think '''''Solen''''' and ''Ensis'' are close relatives, and some think they are similar because of [[convergent evolution]]. The matter will probably be made clear by [[sequence analysis]] in the furure. ==Description== The razor shell has been known to reach {{convert|23|cm|in}}<ref>[http://i9.photobucket.com/albums/a89/Superflid/razor.jpg Large specimen.]</ref> in length. The [[Dorsum (biology)|dorsal]] margin is straight while the [[ventral]] margin is curved. It can easily be confused with the slightly shorter {{convert|15|cm|in}} and more curved ''E. ensis'' (in which both front and back are curved in parallel). Razor shells have a fragile shell, with open ends. The shell is smooth on the outside and whiti