 
 
 200 μm
 200 μm
 400 μm
 400 μm
 600 μm; x 100
 600 μm; x 100
 
 
 
 
 
 
 
 
 
 
 
 
D. gigas:  About 700 μm long; 
macronucleus sausage-shaped; contractile vacuoles line the dorsal surface and extend right to the 
tip of the neck region (Illustrated Guide, 1985).  
D. monilatus (Stokes, 1886) Kahl, 1931:  Elongate; 
700 μm long; no separate tail region; 
macronucleus moniliform; contractile vacuoles line the dorsal surface and extend right to the 
tip of the neck region (Carey, 1992).  Proboscis less than 1/4 of the body length.