OFR 151.pdf - CRC LEME

Casuarinaceae, Cunoniaceae, Elaeocarpaceae and Symplocos. The only ‘frequent’ Proteaceae
is an extinct species, Proteacidites pachypolus (M.K. Macphail unpubl. data).
4. Capricorn Basin
Late Miocene to Early Pleistocene microfloras are co-dominated by Podocarpus-
Prumnopitys, Araucariaceae (Agathis), Casuarinaceae, Myrtaceae, Casuarinaceae and trilete
ferns including Cyathea. Palmae and/or Liliaceae occur in trace numbers: Nothofagus is not
recorded the Late Miocene or Pliocene sections.
5. Northern New South Wales
Palaeovalleys incised into the north-west slopes in New South Wales are filled with Late
Cenozoic colluvium. Independent age control is lacking, although a number of assemblages
include rare taxa that become extinct during the Late Neogene, e.g. Lophosoria. Martin
(1973, 1980, 1981) has proposed that the associated microfloras can be dated as Mid-Late
Miocene, Pliocene and Pleistocene, based on the abundance of Nothofagus (Brassospora) spp.
relative to Asteraceae, Chenopodiaceae-Amarathaceae and Poaceae. For example,
Nothofagus (Brassospora) spp. had become rare or extinct although gymnosperms
(Araucariaceae, Podocarpaceae) continued to dominate stands of gallery rainforest during the
Early Pliocene. By the Late Pliocene, the regional vegetation was dominated by sclerophyll
taxa, Asteraceae and (at one site) Poaceae.
Inferred climate
Climates on the northeastern Queensland coast were very warm (upper mesotherm) and very
wet (perhumid) with a possibly pronounced dry season. Climates at higher elevations on the
Eastern Highlands were cooler (lower mesotherm) and wetter during summer months.
Macphail (1997b) has proposed that the increase in sclerophyll taxa is evidence that regional
climates became increasingly seasonal (possibly monsoonal) during the Late Neogene.
In inland northwestern New South Wales, summer rainfall first fell below the threshold (~200
mm per month) to support Nothofagus during the mid to Late Miocene, possibly earlier in the
north than in the south of the region. Conditions were warm (upper mesotherm) and
relatively wet (humid) during the Early Pliocene but had became cooler (lower mesotherm)
and much drier (subhumid) and/or strongly seasonal during the Late Pliocene.
5.2.3 Central Australia
A probable Late Neogene microflora is preserved in the Tempe Downs T1A borehole, drilled
ca. 160 km north-east of Uluru (Macphail 1996c). This is dominated by Casuarinaceae (70%)
but includes a significant representation of mesophytic taxa, e.g. Araucaria (2%), Dacrydium
(2%), Podocarpus-Prumnopitys (10%) and Cyperaceae (12%). Nothofagus is not recorded but
Lagarostrobos, Eucalyptus, Dodonaea, Epacridaceae and Restionaceae (Milfordia
homeopunctata) occur in trace (