Late Permian

Illwarra Coal Measures

Mudgee, New South Wales, Australia

17mm fruit on 116mm slab

Flower.

Plumsteadia is the name for a fruiting structure on a glossipterid plant.  It is known from Argentina, Australia, and Antarctica, dating back to a time when those three continents (and in fact all of the major landmasses) were connected forming the supercontinent, Pangaea.