Nutrition
Paragnetina media Nymphs posses a quite advanced digestive system
that includes a stomach. This enables them to feed on a
variety of substances, being mostly other consumers. They obtain
and grind their food by using their strong
chewing mandibles on the cephalized portion of their body.
These nymphs are largely carnivorous, secondary consumers mostly
feeding on benthic aquatic insects, but are known to consume
some vegetable matter as well from time to time. Adults,
however, only survive a few weeks and are
herbivores feeding on the grasses located around the
streams.
Some of the main food sources include:
Ephemeroptera- mayfly nymphs, which are mostly
prevalent in spring.
Trichoptera- Caddisflies, which are the only food
present year round.
Diptera- Dipterous larva
Diatoms- the common food for nymphs during the
months of march and April.
Detrius- Detrius are the smallest contributor to the
diet of the nymph.