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New publication on Early Cretaceous terrestrial flora and invertebrate fauna of Victoria just published McLOUGHLIN, S., TOSOLINI, A.-M., NAGALINGUM, N. & DRINNAN, A., 2002. Early Cretaceous (Neocomian) flora and fauna of the lower Strzelecki Group, Gippsland Basin, Victoria. Memoir of the Association of Australasian Palaeontologists 26, 1-144. Abstract Fossil assemblages are described from the Tyers River Subgroup (late Berriasian to Hauterivian), Gippsland Basin, Victoria. The assemblages include plant macrofossils referable to 33 form-species of which five are new (Isoetites abundans Tosolini & McLoughlin, Coniopteris victoriensis Nagalingum & McLoughlin, Otozamites douglasii Drinnan, Brachyphyllum tyersensis Tosolini & Nagalingum, Otwayia hermata Tosolini & McLoughlin) and three are new combinations (Medwellia lacerata [Douglas] Nagalingum & McLoughlin, Rintoulia variabilis [Douglas] McLoughlin & Nagalingum, Pachydermophyllum austropapillosum [Douglas 1969] McLoughlin & Nagalingum). Macrofossil assemblages include representatives of the Hepaticales, Isoetales, Equisetales, Filicopsida, seed-ferns, Coniferales and unionid bivalves. Co-preserved mesofossil suites include dispersed cuticle fragments, seed coats, seed megaspore membranes, microspore clusters, fern leptosporangia, charcoalified wood, resin blebs, epiphyllous fungal shields, clitellate annelid cocoons, insect exoskeleton fragments and coprolites. Sixteen lycophytic megaspore taxa were identified from the succession including six new species (Erlansonisporites confertus Tosolini, Favososporites brevis Tosolini, Hughesisporites australis Tosolini, Paxillitriletes rintoulensis Tosolini, Striatriletes imperfectus Tosolini, Trikonia locmaniensis Tosolini). These represent the first Neocomian megaspores formally described from Australia and their diversity and abundance indicates that lycophytes represented a significant component of the Early Cretaceous vegetation. The Tyers River Subgroup shares some taxa with the well studied Aptian Koonwarra flora of the Gippsland Basin but lacks several key elements (Ginkgoales, angiosperms and large-leafed araucarian conifers) and is more closely comparable to Jurassic floras of eastern Australia in its strong representation of bennettitalean, pentoxylalean and other seed-fern remains. The Tyers River Subgroup flora differs from coeval northwestern Australian floras in containing smaller-leafed bennettites, Komlopteris and Pachydermophyllum species and by the lack of dipteridacean and gleicheniacean/lophosoriacean fern macrofossils. This intra-Australian provincialism is interpreted to be largely a function of palaeolatitude-induced climatic differences. Six major biofacies (one divisible into four sub-facies) are recognized in the Tyers River Subgroup and are attributable to three broad environmental settings within fluvial depositional tracts. Channel deposits host principally detrital plant remains derived from a broad range of riparian, upland and reworked floodbasin communities. Silty floodbasin deposits typically host a mixture of pteridosperm-, fern- and lycophyte-dominated assemblages derived from a mosaic of herb-, shrub- and small tree-dominated communities developed mainly in perennially or seasonally wet environments. Better drained, intervening levee, crevasse splay and neighbouring upland environments are interpreted to have hosted a conifer-dominated flora contributing to conifer-, root/rhizome-, megaspore- and clitellate-rich fossil associations. The floristic diversity, foliar morphology of selected species, strong representation of deciduous taxa and sedimentological data collectively suggest that seasonally cold conditions prevailed during the Neocomian-Aptian compared to the Albian in southeastern Australia. This volume is available from: The Business Manager Geological Society of Australia 706 Thakral House 301 George Street Sydney NSW 2000 AUSTRALIA Tel: (+ 61 2) 9290 2195 Fax: (+ 61 2) 9290 2198 E-mail: misha@gsa.org.au ----------------------------------------------------------------- Dr John R. Laurie Eastern and Onshore Petroleum GEOSCIENCE AUSTRALIA GPO Box 378 Canberra ACT 2601 Australia Tel: (02) 6249 9412; Fax: (02) 6249 9980 E-mail: John.Laurie@ga.gov.au Street Address: Cnr Jerrabomberra Avenue & Hindmarsh Drive Symonston ACT 2609 ABN 80 091 799 039 -----------------------------------------------------------------
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