Syngamus trachealis

from The Collaborative International Dictionary of English v.0.48

Gape \Gape\, n.
   1. The act of gaping; a yawn. --Addison.
      [1913 Webster]

   2. (Zool.) The width of the mouth when opened, as of birds,
      fishes, etc.
      [1913 Webster]

   {The gapes}.
      (a) A fit of yawning.
      (b) A disease of young poultry and other birds, attended
          with much gaping. It is caused by a parasitic nematode
          worm ({Syngamus trachealis}), in the windpipe, which
          obstructs the breathing. See {Gapeworm}.
          [1913 Webster]