The Proteaceae fossil wood record in Australia and a new species associated with Oligocene volcanism from the Bunya Mountains Volcanic Province in south-eastern Queensland

A new species of fossil wood, Scalarixylon lahar Leggate, Fabillo & Rozefelds sp. nov., is described from Oligocene volcaniclastics associated with the Bunya Mountains Volcanic Province near Maidenwell in south-eastern Queensland. It shares wood characters, including wide rays and narrow bands of abaxially placed axial parenchyma that curve inwards between the large rays, with fossil Proteaceae wood from South America, suggesting that these taxa can be collectively referred to the subfamily Grevilleoideae. The fossil species, particularly those from South America, share some features with extant genera but cannot be confidently placed within an extant tribe or genus within the family. This uncertainty is due to gaps in our knowledge of extant wood anatomy across the family and a lack of phylogenetic studies utilising wood anatomy in the Proteaceae. Wood anatomical features and leaf morphological characteristics indicate that the fossil flora at Maidenwell was growing under ever-wet, mesic conditions and was dominated by rainforest taxa. The status of grevilleoid wood that was described as Banksia fossilis R.T.Patton from Bacchus Marsh in Victoria is unclear as the original description is incomplete and the whereabouts of the type material is not known.