Gametocytes of a polychromophilid parasite indistinguishable from those of P. melanipherus are commonly found in the blood of the bent-winged bat Miniopterus schreibersii in New South Wales. There is a seasonal variation in infection rate, this being lowest in April (0%) and highest in August (up to 82·7%), and in density of parasitaemia.
This variation is the reverse to that found in the same species of bat in the northern hemisphere.
The reproductive biology of M. schreibersii in New South Wales is considered in relation to the seasonal variation in infection rate.
The main vectors of the parasitism are likely to be the nycteribiid flies, Penicillidia oceanica and Nycteribia parilis n.ssp.