The Pharidae Family includes 68 species comprising 4 subfamilies (Pharellinae (6 genus), Cultellinae (6), Pharinae (3), Siliquinae (1))
and 16 genus (Siliqua (18 species), Ensis (14), Ensiculus (6), Sinupharus (5), Pharella (5), Cultellus (5), ...)

Phylum      : Mollusca
 Class       : ⤷Bivalvia 
  Subclass    : ⤷Autobranchia 
   Infraclass  : ⤷Heteroconchia 
    Subterclass : ⤷Euheterodonta 
     Superorder  : ⤷Imparidentia 
      Order       : ⤷Adapedonta 
       Superfamily : ⤷Solenoidea 
        Family      : ⤷Pharidae

Common name : razor shells or jackknife clams

Aspect : equivalently valved, elongated, narrow, and cylindrical or slightly curved; gape at both ends (anterior and posterior); small and simple hinge with few teeth (typically 1–2 cardinal teeth in each valve); smooth surface with fine growth lines; shell length usually 5–20 cm, some species (Ensis magnus) up to 28 cm

Feeding : filtration of microorganisms in suspension (phytoplankton, zooplankton, detritus, and organic particles)

Environment : cosmopolitan, found worldwide in temperate and tropical coasts in intertidal to shallow subtidal zones (0–50 m) in sandy or fine-muddy substrates (as very fast burrowers they use a strong, muscular foot to “jump” and dig downwards 30–60 cm deep in seconds when disturbed)