The authors have described the histological strusture of oesophagus, stomach and pyloric caeca from Semaprochilodus insignis, on ilyphagus freshwater fish from the central Amazon.
The oesophagus presents in the first portion a stratified, non glandular epithelium and in the second portion a colwnnar one, with mucous secreting cells, wile the stomach shows a descendent portation with glandular mucosa and an ascendent with a very thick wall. The pyloric caeca, very numerous, have unknown function.
The digestive tube structure of S. insignis is related to their feeding habit, and hypothesis are propesed about digestion food mechanism.