Food captured by the corona enters the mouth and passes to the pharynx until it reaches the mastax (a pouch like sac with muscles and the trophi). Some rotifers have salivary glands to aid the digestion process. After the food is processed by the mastax, it continues to pass through the esophagus, then the stomach (sometimes with gastric glands) and later through the intestine and the anus.

• The mastax consists of hard chitinous structures or jaws (named trophi) whose shape and design varies according to the species of rotifer.
  The trophi is composed of seven pieces:
       - fulcrum (unpaired),
       - paired rami (singular: ramus),
       - paired unci (singular: uncus) and
       - paired manubria (singular: manubrium).
  
• The mastax with its trophi varies widely from species to species according to their feeding habits.
• The trophi is adapted for
       - grinding particulate detritus (malleate or ramate), or
       - capture and tearing of prey (forcipate or incudate), or
       - extract fluids from plants or from other microscopic organisms (virgate), or
       - scraping organic particle surfaces (forcipate, virgate, malleate).
  

More about
Rotifer Bauplan
Rotifer classification
Rotifer reproduction