title: Nuculanida
text: # Nuculanida
  
  Nuculanida is an order of very small saltwater clams, marine bivalve molluscs in the subclass Protobranchia.
  
  ## Description
  
  These bivalves are distinguished by the presence of relatively primitive, "protobranchiate" gills. There are a row of short teeth along the hinge of the shell. The shells are often internally nacreous.
  
  ## Families
  
  Families within the order Nuculanida include:
  
  * Bathyspinulidae Coan & Scott, 1997
  * Lametilidae
  * Malletiidae H. and A. Adams, 1858
  * Neilonellidae Schileyko, 1989
  * Nuculanidae H. Adams & A. Adams, 1858
  * Sareptidae Stoliczka, 1871
  * Siliculidae Allen and Sanders, 1973
  * Tindariidae Verrill and Bush, 1897
  * Yoldiidae Habe, 1977
  * Praenuculidae Mcalester, 1969 (?)
  * Pristiglomidae Sanders and Allen, 1973 (?)
  