The earliest Triassic, Coal Cliff Sandstone (basal Narrabeen Group) in the roof shales to the latest Permian Bulli Coal in the Southern Coalfield of New South Wales, Australia, contains a depauperate flora of ferns, lycopsids, conifers and seed ferns, that survived the greatest mass extinction of all time at the Permian-Triassic boundary. Only one taxon of seed fern is known from this flora and its affinities have been unclear until recent discovery of its reproductive organs. The leaves are coriaceous, bipinnate and bipinnatifid, and its terminal unipinnate rachides show multiple dichotomies of the rachis. These leaves were referred to "Thinnfeldia" callipteroides", based on type material from the earliest Triassic, Sakamena Group of Madagascar, by John Townrow. However, the stomatal apparatus of the leaves is cyclocytic with papillate subsidiary cells, quite distinct from the doubly cyclocytic non-papillate subsidiary cells of Middle to Late Triassic Thinnfeldia, and identical to the stomatal apparatus of Lepidopteris. Despite this cuticular similarity, Mary White has used rachis dichotomies as a character to transfer these leaves to "Dicroidium" callipteroides. Newly discovered ovulate fructifications of this taxon consist of branching systems of peltate ovular heads each with about 10 distinct marginal lobes, referrable to the genus Peltaspermum. In a large collection of these fructifications no more than 2 ovules were seen per head, although it is possible that others had been abscised. Microsporophylls also were found, and are still under investigation, but are also compatible with peltasperm rather than corystosperm affinities. This taxon of seed fern shows clear affinities to European peltasperms, and probably invaded Gondwanaland from the north during earliest Triassic postapocalyptic greenhouse of the earliest Triassic. It is also a plausible ancestor of corystosperms such as Dicroidium, which first appears higher within the Narrabeen Group (upper Bulgo Sandstone) in the Southern Coalfield of New South Wales.

Key words: Australia, Dicroidium, Peltaspermum, pteridosperm, Triassic