Monpeelyata (Oligocene to of Australia)

Where: Tasmania, Australia (42.1° S, 146.7° E: paleocoordinates 54.3° S, 145.9° E)

• coordinate stated in text

When: Upper Proteacidites tuberculatus pollen zone, Late/Upper Oligocene to Late/Upper Oligocene (28.4 - 16.0 Ma)

• The sediments are regarded as probably late Oligocene or early Miocene age based on analysis of microflora and radiometric dates of closely associated basalts (Hill & Gibson, 1986).

•The area has been dated using K-Ar analysis, the age range 23.6-21.8 Myr (Sutherland et al. 1973).These results agree with the palynological data, and an earliest Miocene age is therefore proposed for the Monpeelyata deposit, with the probable age falling within the period 21.8-23.6 Myr (M.K. Macphail, personal communication).

•The age of Monpeelyata is based on a combination of palynological data and K-Ar dates on basalt flows in the area surrounding Great Lake. Both sets of data point to the Monpeelyata flora being no younger than earliest Miocene. The maximum age is less well defined although the absence of a large number of species found in Oligocene palynoflora in northern Tasmania (Hill & Macphail, 1983; Hill, 1987) suggests that the flora is unlikely to be older than the (latest?) Late Oligocene. (Macphail and Hill, 1991)

Environment/lithology: lacustrine; gray mudstone

• It is probable that the depositional environment was a shallow freshwater lake or tarn similar to the many alpine lakes which currently occur in the Tasmanian highlands (Hill 1988).

•Abundant remains of the freshwater hydrophyte Isoetes (Hill, 1988) and the fine grain size of the emergent sedimentary rock indicate a low energy depositional environment, probably a shallow pond, a sluggish river channel, or less likely a shallow, sheltered lake bay, subaerially exposed before or during lava extrusions. (Macphail and Hill, 1991)

• The fossils occur in a mudstone lens approximately 15 m long and about 1.5 m thick which has been exposed in a channel-cutting on the Central Plateau. The lens is overlain by about 2 m of basalt.

•The plant fossils described by Macphail and Hill 1991 come from a mudstone exposed in the west wall of the Monpeelyata Canal which diverts water from the Ouse River into the Lake Echo hydroelectic impoundment. The exposure occurs directly next to the bridge on the Monpeelyata Canal service road. The mudstone lens forms part of a thin (<2 m?) concave lenticular sedimentary sequence that overlies Jurassic dolerite and is overlain by massive to vesicular, alkali olivine basalt. (Macphail and Hill, 1991)

Size classes: macrofossils, microfossils

• Several female cones were retrieved from the mudstone.

Preservation: adpression

Collection methods: bulk, sieve,

Primary reference: R. S. Hill. 1987. Tertiary Isoetes from Tasmania. Alcheringa 12(2):157-162 [C. Jaramillo/C. Jaramillo]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 167314: authorized by Carlos Jaramillo, entered by Carlos Jaramillo on 11.03.2015

Creative Commons license: CC BY (attribution)

Taxonomic list

• 830 podocarpaceous specimens.
Banksieacidites cf. elongatus5
aff. Tribe Banksieae (Proteaceae)
aff. Dryptopollenites sp.5
unknown angiosperm
Herkosiporites elliotii5
extinct fern ally / spores
Lateropora glabra5
aff. Freycinetia (Pandanaceae)
Microelatidites palaeogenicus5
aff. Phyllocladus
Striasincolpites laxus5
aff. Liparophyllum/Villarsia
 Pinales - Podocarpaceae
Dacrycarpites australiensis5 Cookson and Pike 1953
aff. Dacrycarpus
Lygistepollenites florinii5 Stover and Evans 1973
aff. Dacrydium (Group B sp.)
Dacrycarpus lanceolatus6 Wells and Hill 1989
n. sp.
Dacrycarpus involutus6 Wells and Hill 1989
n. sp.; 164 specimens.
Dacrycarpus acutifolius6 Wells and Hill 1989
n. sp.; 274 specimens.
Phyllocladidites mawsonii5 Cookson 1947
aff. Lagarostrobus franklinii
Phyllocladidites cf. verrucosus5 Stover and Evans 1973
aff. Lagarostrobus
Podocarpidites spp.5 Cookson 1947
(min. 3 sp.) aff. Podocarpus s.l.
Parvisaccites catactus5
aff. Halocarpus bidwillii
Microstrobos microfolius6 Wells and Hill 1989
n. sp.
Podosporites erugatus5
aff. Microstrobos
Podosporites microsaccatus5 Dettmann 1963
unknown gymnosperm
Microcachryidites antarcticus5 Couper 1953
aff. Microcachrys tetragona
 Pinales - Cupressaceae
Cupressaceae "type"5 Martynov 1820
Fitzroya tasmanensis4 Hill and Whang 1996
 Pinales - Araucariaceae
Dilwynites granulatus5
aff. Araucariaceae
Dilwynites cf. tuberculatus5 Harris 1965
aff. Araucariaceae
Araucariacites australis5 Cookson 1947
aff. Araucariaceae
Araucaria planus1 Hill 1990
n. sp.
Araucaria prominens1 Hill 1990
n. sp.
Araucaria uncinatus1 Hill 1990
n. sp.
 Cyperales - Commelinidae
Cyperaceae indet.5 Jussieu 1789 sedge
 Restionales - Commelinidae
Milfordia hypolaenoides5
aff. Restionaceae
? Milfordia homeopunctata5 Partridge 1973
aff. Restionaceae
 Typhales - Commelinidae
Sparganiaceae "type"5 Hanin
cf. Sparganium
 Liliales - Liliidae
Liliacidites spp.5 Couper 1953
aff. Liliaceae - (3)
Liliacidites lanceolatus5 Stover 1973
aff. Liliaceae
 Poales - Poaceae
Graminidites media5 Cookson 1947
aff. Poaceae
  - Polypodiaceae
Laevigatosporites ovatus5 Wilson and Webster 1946
aff. Blechnaceae / spores
Cyathidites splendens5
aff. Cyathea /Spores
Cyathidites minor5 Couper 1953
aff. Cyathea /Spores
Cyathidites cf. paleospora5 Alley and Broadbridge 1992
aff. Cyathea /Spores
Matonisporites ornamentalis5 Partridge 1973
aff. Dicksonia antarctica
 Gleicheniales - Matoniaceae
Dictyophyllidites cf. arcuatus5 Pocknall and Mildenhall 1984
aff. Gleicheniaceae
 Cyatheales -
Cyatheacidites annulatus5 Cookson 1947
aff. Lophosoria quadripinnata /Spores
Baculatisporites sp.5 Thomson and Pflug 1953
aff. Hepaticae /Spores
Foveotriletes palaequetrus5 Partridge 1973
aff. Lycopodium australianum
  - Lycopodiaceae
Latrobosporites crassus5 Harris 1981
aff. Lycopodiaceae / spores
Lycopodiumsporites spp.5 Delcourt and Sprumont 1955
  - Isoetaceae
Isoetes reticulata n. sp. Hill 1987
Malvacipollis subtilis5 Stover 1973
aff. Euphorbiaceae
Gambierina rudata5
Late Cretaceous-Paleocene (reworked?)
Ericipites scabratus5 Harris 1965
aff. Epacridaceae/Ericaceae
Tricolporites sp.5 Cookson 1947
Tricolporites spp.5 Cookson 1947
min. 3 sp., unknown angiosperms.
 Nepenthales - Dilleniidae
Droseraceae indet.5 Salisbury 1808
aff. Drosera
 Theales - Dilleniidae
Ilexpollenites anguloclavatus5 McIntyre 1968
aff, Ilex
 Polygonales - Caryophyllidae
Polycolporopollenites esobalteus5 Pocknall and Mildenhall 1984
aff. Polygalaceae
Haloragacidites harrisii5 Mildenhall and Harris 1971
aff. Casuarinaceae
Periporopollenites polyoratus5
aff. Caryophyllaceae?
Periporopollenites demarcatus5 Stover 1973
aff. Trimeniaceae?
 Myrtales - Myrtaceae
Eucalyptus sp.5 Lheritier 1789
Possibly modern
 Myrtales -
Myrtaceidites eucalyptoides5
aff. Eucalyptus
Myrtaceidites spp.5 Cookson and Pike 1960
Myrtaceidites parvus; Myrtaceidites mesonesus
Myrtaceidites sp.5 Cookson and Pike 1960
aff Myrtaceae
 Apiales - Apiaceae
Apiaceae spp.5 Lindley 1836
min. 3 sp. Modern affinity: including Dichosciadium ranunculaceum
 Caryophyllales -
aff. Lymingtonia sp.5 Erdtman 1960
aff. Portulacaceae?
 Proteales -
Proteacidites cf. stratosus5
aff. Proteaceae
Proteacidites spp.5 Cookson and Couper 1953
aff. Proteaceae
Proteacidites cf. obscurus5 Cookson 1950
aff. Proteaceae
 Fagales - Nothofagaceae
Nothofagus microphylla n. sp.2 Hill 1991
Nothofagus gunnii2 Oersted 1873
 Fagales -
Nothofagidites deminutus5
aff. Nothofagus brassii type c
Nothofagidites emarcidus5
aff. Nothofagus brassii types a &b
Nothofagidites vansteenisii5
aff. Nothofagus brassii type c
Nothofagidites brachyspinulosus5 Harris 1965
aff. Nothofagus fusca type a
Nothofagidites falcatus5 Hekel 1972
aff. Nothofagus brassii type a
Nothofagidites asperus5 Cookson 1958
aff. Nothofagus menziesii-type
Nothofagidites flemingii5 Potonie 1960
aff. Nothofagus fusca type b
Tricolpites sp.5 PotoniƩ 1960
Tricolpites spp.5 PotoniƩ 1960
unknown angiosperms.
Polycolpites sp.5 Couper 1953
Unknown angiosperm aff. Mentha
Austrocedrus tasmanica3 Hill and Carpenter 1989
n. sp.; Ovulate cone