Tetraxylopteris Beck emend. Hammond and Berry (2005), the first aneurophytalean genus recorded in Australia

• Aneurophytales are reported from the Bunga beds in New South Wales, Australia.
• The branching pattern of the specimens is a characteristic of the genus Tetraxylopteris.
• Vegetative specimens have distinctive ultimate appendages suggestive of a new species.
• Fossil plant evidence suggests a Givetian to Frasnian age for the Bunga beds.

The Middle to early Late Devonian aneurophytalean progymnosperms represent the basalmost group of lignophytes and may have included the seed plant ancestor. They are widely recorded in Laurussia. Before this work, the only occurrences of Aneurophytales in Gondwana were in Venezuela and Morocco. In this paper we describe one fertile and two vegetative specimens of Tetraxylopteris from the Bunga beds at Bunga Pinch Quarry, a locality near Tathra on the south coast of New South Wales. The vegetative specimens consist of two orders of axes, the last order bearing alternately arranged ultimate appendages. Ultimate appendages are three-dimensional, highly dissected, and composed of terete segments of unequal length. The shape and arrangement of the ultimate appendages suggest that the Australian specimens belong to a new species of Tetraxylopteris. The association of Tetraxylopteris with large lycopsids constrains the age of the Bunga beds to the Givetian–Frasnian interval. The range of dissected ultimate appendage morphologies displayed by the genus Tetraxylopteris may have been advantageous in habitats characterized by high light conditions. These morphologies do not show any specialization for lianescence.

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