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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 including five new species (Isoetites abundans Tosolini & McLoughlin, Coniopteris victoriensis Nagalingum & McLoughlin, Otozamites douglasii Drinnan, Brachyphyllum tyersensis Tosolini & Nagalingum, Otwayia hermata Tosolini & McLoughlin) and three 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 newly described 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 Koonwarra Fossil Bed (Aptian) 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 by possession of 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.
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... The present material is similar to Arber's Sphenopteris otagoensis and probably also to his sterile Coniopteris hymenophylloides. The Australian Sphenopteris travisii (Stirling, 1900;Drinnan and Chambers, 1986;McLoughlin et al., 2002) is regarded as identical and has priority. In terms of lobe shape and dissection, Catlins Sphenopteris do not compare well with any of the Hope Bay (Gee, 1989;Rees and Cleal, 2004) species. ...
... Rees and Cleal (2004) argued the distinction between Ptilophyllum and Otozamites was probably artificial and that they "likely belonged to a 'natural' genus." In terms of pinnule shape and venation, the closest morphological match of the Catlins material is with Otozamites douglasii from the Lower Cretaceous of Victoria (McLoughlin et al., 2002), and although epidermal details are needed to be sure, the Catlins material is assigned to that species. However, there may be more than one species. ...
... Genus RINTOULIA McLoughlin, Tosolini, Nagalingum, and Drinnan, 2002 Rintoulia pectinata (Hector) McLoughlin, Tosolini, Nagalingum, and Drinnan, 2002 Figure 11 1886 Lomarites pectinata Hector, fig. 30A (5). ...
... and Australia (e.g. Walkom, 1921;Florin, 1952;Townrow, 1967;McLoughlin, 1996;McLoughlin et al., 2002;McLoughlin and Pott, 2009;etc.), from 15°S to 85°S palaeo-latitude, but most occurrences are concentrated between 45°S and 60°S ( Fig. 4; Table 1). ...
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... Furthermore, possible descendants have also been described from the Cretaceous of Mongolia (Shi et al. 2016;Shi et al. 2019). Various other predominantly Gondwanan genera (e.g., Komlopteris Barbacka 1994, Rintoulia McLoughlin et Nagalingum 2002 of Jurassic to Eocene age have unforked but otherwise similar leaf forms, venation and cuticle morphology (Maheshwari 1986;McLoughlin et al. 2002;McLoughlin et al. 2008), collectively attesting to a much greater stratigraphic range and significance of Umkomasiales in the Mesozoic vegetation than appreciated previously. ...
... The early Cretaceous floras are widespread in other areas of Gondwana, being known from, South America (Archangelsky, 1963(Archangelsky, , 2001Cúneo et al., 2010;Kunzmann et al., 2004), South Africa (Anderson & Anderson, 1985), Australia (Douglas, 1969;Drinnan & Chambers, 1986;Hills, 1994;McLoughlin, 1996;McLoughlin et al., 2000McLoughlin et al., , 2002 and Antarctica (Gee, 1989;Bose et al., 1991;Césari, et al., 1998;Cantrill, 1995Cantrill, , 1996Cantrill, , 1997Cantrill, , 2000. The early Cretaceous flora from the Antarctica and Australia shows local variations depending on preservation potential. ...
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... Paxillitriletes ( Mädler (1954), which had been used previously for an extant angiosperm genus in Araceae by Wallich (1830Wallich ( -1832, currently contains about 27 species (Table 3; Kovach and Batten, 1989;Batten and Kovach, 1990;Batten and Koppelhus, 1993;McLoughlin et al., 2002;McLoughlin et al., 2014;Li et al., 2021). Nine species of Paxillitriletes have well-developed reticulate ornament on their distal surfaces. ...
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... These trees formed an overstory above a fernrich understory that also contained shrubby seed plants . Older floras also include Ginkgoales, whereas those on the basin margins were rich in Bennettitales (Douglas 1969;McLoughlin et al. 2002). The most striking aspect of this vegetation is the diversity and abundance of ferns and bryophytes (Douglas 1973;Drinnan and Chambers 1986). ...
Chapter
Full-text available
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... This study's palynological zonation suggests that assemblages from the older Group 1 sites are slightly older than those from the Group 2 sites with no discernible gap in the stratigraphy and that the base and top of the P. notensis Zone (sensu Morgan et al. 1995) are not present. Our work confirms the suggestion of McLoughlin et al. (2002) that there may be a hiatus between the Tyers River Subgroup and the 'Wonthaggi Formation' in the Gippsland Basin. Group 1 sites (upper Barremian strata) include those in the San Remo area, the Kilcunda Coal Seam and The Arch, Black Head, Harmers Haven sites 1-8, the 'Honey Locality' and all sites in the Caves and Flat Rocks region (Fig. 7A, B, Table 2). ...
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