Eucryphia (Cunoniaceae) reproductive and leaf macrofossils from Australian Cainozoic sediments
Barnes, RW and Jordan, GJ, Eucryphia (Cunoniaceae) reproductive and leaf macrofossils from Australian Cainozoic sediments, Australian Systematic Botany, 13, (3) pp. 373-394. ISSN 1030-1887 (2000) [Refereed Article]
The first Fossil capsule of Eucryphia, E. reticulata R.W.Barnes and G.J.Jord. sp. nov., is described from Lea River (Early Oligocene), and, like capsules of the two extant South American species or E. glutinosa (Poepp. et Endl.) Baill. and E. cordifolia Cav., is large and has a relatively large number of valves. The capsule occurs with a Eucryphia leaf macrofossil that was probably a leaflet from a compound leaf as it is highly falcate. The leaflet may be derived from the same parent plant as E. reticulata but in the absence of an organic connection it is described as a new species, E. leaensis R.W. Barnes and G.J. Jord. sp. nov. Additional leaf macrofossil specimens of E. aberensis R.S. Hill from the type locality (Loch Aber; Middle - Late Eocene) and a new locality record for the species, Little Rapid River (Early Oligocene), indicate that the species had compound leaves formed by serrate and entire margin leaflets. Another incomplete Eucryphia capsule occurs at Little Rapid River (Early Oligocene) but it is too poorly preserved to assign it to an extant or extinct species. It may be derived from the same parent plant as E. 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 and G.J. Jord. sp. nov., is also described from? Latest Eocene - Early Oligocene sediments at Wilson's Creek, central Tasmania. Leaf macrofossils previously assigned to E. aff. milliganii from Early Pleistocene sediments at Regatta Point in western Tasmania are shown to be conspecific with the two extant Tasmanian species, E. lucida (Labill.) Baill. and E. milliganii Hook.f. ssp. milliganii on the basis of foliar hair distribution patterns and density. The oldest fossil Eucryphia species, E. falcata R.S. Hill (Lake Bungarby; Late Paleocene), had compound leaves formed by leaflets with serrate margins, which is possibly the plesiomorphic condition for all Cunoniaceae genera. Within Eucryphia, there has been an evolutionary trend towards simple leaves with entire margins and well-developed peltiform cuticular extensions.