pectinibranchiata

from The Collaborative International Dictionary of English v.0.48

Pectinibranchiata \Pec`ti*ni*bran`chi*a"ta\, n. pl. [NL. See
   {Pecten}, and {Branchia}.] (Zool.)
   A division of Gastropoda, including those that have a
   comblike gill upon the neck.
   [1913 Webster]