This plant is obviously a member of the Asteraceae, but I can't find
it in my book on Australian weeds. I don't think it is a native.

It grows in fairly dense stands under Casuarina trees on the flood
plain of a river in a warm temperate area of inland NSW (Bathurst). It
is just coming into flower now (mid summer).

Associated plants are Hemlock and Bidens (Cobbler's Pegs).

http://www.box.net/shared/static/0k5e2o4bo4.jpg

Apologies for the rather inadequate picture of the composite flower.