Eucryphia (Cunoniaceae) reproductive and leaf macrofossils from Australian cainozoic sediments

Abstract

The first fossil capsule of Eucryphia,E. reticulata R.W.Barnes & G.J.Jord. sp. nov.,is described from Lea River (Early Oligocene), and, like capsules of the twoextant South American species of E. glutinosa (Poepp. etEndl.) Baill. and E. cordifolia Cav., is large and has arelatively large number of valves. The capsule occurs with aEucryphia leaf macrofossil that was probably a leaflet from a compound leaf as it is highly falcate. The leaflet may be derived fromthe same parent plant as E. reticulata but in theabsence of an organic connection it is described as a new species,E. leaensis R.W.Barnes & G.J.Jord. sp. nov.Additional leaf macrofossil specimens of E. aberensisR.S.Hill from the type locality (Loch Aber; Middle–Late Eocene) and anew locality record for the species, Little Rapid River (Early Oligocene),indicate that the species had compound leaves formed by serrate and entiremargin leaflets. Another incomplete Eucryphia capsuleoccurs at Little Rapid River (Early Oligocene) but it is too poorly preservedto assign it to an extant or extinct species. It may be derived from the sameparent plant asE. aberensis, with which it occurs, but cannot be confirmed as there is no organic connection. A new leaf macrofossil with serrate margins, E. mucronata R.W.Barnes & G.J.Jord. sp. nov., is also described from ?Latest Eocene–EarlyOligocene sediments at Wilson’s Creek, central Tasmania. Leafmacrofossils previously assigned to E. aff.milliganii from Early Pleistocene sediments at RegattaPoint in western Tasmania are shown to be conspecific with the two extant Tasmanian species, E. lucida (Labill.) Baill. andE. milliganii Hook.f. ssp.milliganii on the basis of foliar hair distribution patterns and density. The oldest fossil Eucryphiaspecies, E. falcata R.S. Hill (Lake Bungarby; LatePaleocene), had compound leaves formed by leaflets with serrate margins, whichis possibly the plesiomorphic condition for all Cunoniaceae genera. WithinEucryphia, there has been an evolutionary trend towardssimple leaves with entire margins and well-developed peltiform cuticular extensions.