Digestive system of an Astyanax fry. A A live specimen photographed in the Pachón cave. Note the healthy-looking appearance of this juvenile, the two parts of the inflated swim bladder, the almost completely degenerated eye, and the digestive system filled with food. Scale bar as in B. B Body, with the digestive system exposed C Stomach and intestine. Notice that the food content can be seen through the translucent walls. All fish studied were well fed and their guts were full of food.