[2] Like many Sciomyzidae, species of this genus have larvae that are predators or parasitoids of snails.

The larva of P. albovaria, for example, eats land snails such as Anguispira alternata and A. fergusoni, and then pupates in the empty shell.

[3] The P. albocostata larva eats up to five snails and then pupates in the ground litter next to the last empty shell.

[4] The larva of P. inflexa attacks the glass snail Zonitoides arboreus.

[6] P. anubis larvae feed on several types of freshwater snails along the edges of ponds and marshes.