Mary E. Dettmann

Phylogeny and biogeography of Ruffordia, Mohria and Anemia (Schizaeaceae) and Ceratopteris (Pteridaceae): evidence from in situ and dispersed spores

Sporangia and in situ spores of Cretaceous-Tertiary fertile macrofossils allocated to Anemia, Pelletixia, Ruffordia, Mohriopsis, Schizaeopsis, Schizaeangium, and Schizaeopteris are compared with sporangial and spore types in extant Anemia and Mohria (Schizaeaceae), and Ceratopteris (Pteridaceae). Trilete, cicatricose to canaliculate spores characteristic of extant Anemia are identified in fossil Anemia colwellensis Chandler, Anemia fremontii Knowlton forma fertilis Andrews, Pelletixia valdensis (Seward) Watson & Hill, Pelletixia amelguita Skog, and Russian specimens of Ruffordia goeppertii (Dunker) Seward; smooth-walled spores occur in Anemia poolensis Chandler. English Ruffordia goeppertii have spores that are morphologically intermediate between those of extant Anemia and Ceratopteris, but sporangial features confirm alliance with the Schizaeaceae. Sporangia are unknown from fossil Schizaeopsis americana Berry, and its spores are distinct from those of extant ferns. Distally annulate sporangia consisten...

The Antarctic/Australian rift valley: Late cretaceous cradle of nortteastern Australasian relicts?

The montane vegetation of northeastern Australasia represents a modified sample of the late Cretaceous flora that fringed the embryonic Southern Ocean in the southern Australasian/Antarctic region. Beauprea, Knightia, Macadamia, Gevuina and/or Hicksbeachia (Proteasceae), Gunnera (Gunneraceae), Ilex (Aquifoliaceae), Winteraeae, Epacridaceae, Trimeniaceae, Nothofagus (brasii group), Araucariaceae, Podocorpus, Dacrydium and Dacrycarpus (Podocarpaceae) are confirmed in the Campanian-Maastrichtian pollen record of estuarine sediments in the Otway Basin, southeastern Australia. The primative angiosperms migrated there by individualistic routes after Early Cretaceous appearances in northern Gondwana and southern Laurasia; other taxa evolved in austral regions. Evidence is advanced for origin of Ilex, Beauprea, Knightia and Gevuina/Hicksbeachia in southern Australia/Antarctica during early phases (Late Cretaceous) of opening of the Southern Ocean.

Morphology and ultrastructure of elater-bearing pollen from the Albian to Cenomanian of Brazil and Ecuador: implications for botanical affinity

Abstract The morphological range of elaterate pollen grains is reassessed on the basis of detailed light, scanning electron and transmission electron microscope analyses of representatives from upper Albian–Cenomanian sections in Brazil and Ecuador. Included in the elaterate complex are Alaticolpites , Elaterocolpites , Elateroplicites , Elateropollenites , Elaterosporites , Galeacornea , Pentapsis , Regalipollenites , Senegalosporites and Sofrepites . All possess elater-like protuberances, but are otherwise morphologically disparate. Ultrastructural analyses of three taxa, Elateroplicites africaensis , Elaterosporites klaszii and Sofrepites legouxiae , reveals granular-alveolate ektexine and wall organization comparable to that of gnetalean pollen and to fossil Equisetosporites / Ephedripites . A correlation exists between diversity/frequency levels of Elaterates and successive events in opening of the northern part of the South Atlantic Ocean. This is interpreted to reflect rapid diversification of the gnetalean sources of elaterate pollen in response to climatic perturbations associated with opening and enlargement of this ocean. The introduction and diversification of Elaterates coincides with early phases of angiosperm diversification, whereas extinction of the Elaterates-producing gnetalean group at the close of the Cenomanian heralded the rise to dominance of angiosperms in low latitudinal areas fringing the northern South Atlantic.

Pollen of proteaceous-type from latest Cretaceous sediments, southeastern Australia

Abundant and diverse proteaceous-like triaperturate pollen from Campanian-Maastrichtian sediments in the Otway Basin, southeastern Australia are systematically documented and compared with pollen of extant Proteaceae. Segregation of fossil and extant pollen types has been effected on apertural characters of which six states have been identified. Apertures are colpoid, poroid or porate. Pores of Propylipollis Martin & Harris, 1974 conform with those of subfamilies Grevillioideae and Carnarvonioideae. Colpoids of Beaupreaidites Cookson emend. Martin, 1973, poroids of Lewalanipollis gen. nov., and pores of Cranwellipollis Martin & Harris, 1974 are represented in subfamilies Proteoideae and Persoonioideae. Pores of Proteacidites Cookson ex Couper, 1953 occur in subfamilies Proteoideae and Sphalmioideae. In the Otway Basin fossil record, triporate apertures appear earlier than tricolpoids, triporoids and biporates; and diversity levels of proteaceous pollen are higher than reported from elsewhere implying the ...

Airborne Pinus pollen in the atmosphere of Brisbane, Australia and relationships with meteorological parameters

Relationships between weather parameters andairborne pollen loads of Pinus inBrisbane, Australia have been investigated overthe five-year period, June 1994–May 1999.Pinus pollen accounts for 4.5% of the annualairborne pollen load in Brisbane where thePinus season is confined to the winter months,July–early September. During the samplingperiod loads of 11–>100 grains m3 wererecorded on 24 days and 1–10 grains m3 on204 days. The onset and peak dates wereconsistent across each season, whereas the enddates varied. The onset of the Pinuspollen season coincided with the coolestaverage monthly temperatures (< 22°C),lowest rainfall (< 7mm), and four weeks afterdaily minimum temperatures fell to 5–9°Cin late autumn. Correlations obtained betweendaily airborne Pinus pollen counts andtemperature/rainfall parameters show thatdensities of airborne Pinus pollen arenegatively correlated with maximum temperature(p < 0.0001), minimum temperature (p < 0.0001)and rainfall (p < 0.05) during the mainpollination period. The mean duration of eachpollen season was 52 days; longer seasons wereshown to be directly related to lower averageseasonal maximum temperatures (r2 = 0.85,p = 0.025). These results signify that maximumand minimum temperatures are the majorparameters that influence the onset andduration of the Pinus pollen season inthe environs of Brisbane. Respiratory allergyis an important health issue in Brisbane,Australia, but it remains unknown whether ornot airborne Pinus pollen is acontributing factor.

Airborne pollen of Brisbane, Australia: a five-year record, 1994-1999

The seasonal incidence of pollen in the atmosphere of Brisbane has been established from a near-continuous, volumetric trapping program over the five-year period, July 1994-June 1999. Grass pollen accounts for 71.6% of the average annual pollen load with highest densities (up to 150 grains/m 3 ) recorded in summer and autumn. Significant contributions were also made by taxa of the Cupressaceae (8.7%) and Urticaceae (1.8%) during spring and of the Pinaceae (4.5%) during winter. Pollen seasons of the Casuarinaceae (6.5%) and Myrtaceae (3.2%) are more extended, the former peaking in late winter and the latter in late spring. The onset and duration of the Poaceae and Urticaceae seasons varied from year to year, being later when precipitation levels were low in the late spring-early summer months. Total pollen numbers and grass pollen densities are substantially less than those recorded from southern Australia. Nevertheless, respiratory disease in Brisbane affects up to 10% of the population, and airborne pollen of Poaceae, Urticaceae, Cupressaceae, Pinaceae, and Myrtaceae have been implicated in the release of allergens.

Macrofossil evidence of early sporophyte stages of a new genus of water fern Tecaropteris (Ceratopteridoideae: Pteridaceae) from the Paleogene Redbank Plains Formation, southeast Queensland, Australia

Rozefelds, A.C., Dettmann, M.E., Clifford, H.T. & Lewis, D., August 2015. Macrofossil evidence of early sporophyte stages of a new genus of water fern Tecaropteris (Ceratopteridoideae: Pteridaceae) from the Paleogene Redbank Plains Formation, southeast Queensland, Australia. Alcheringa 39,. ISSN 0311-5518. Water fern foliage is described from the Paleogene Redbank Plains Formation at Dinmore in southeast Queensland. The material, which is based upon leaf impressions, records early sporophyte growth stages. The specimens occur at discrete levels in clay pits at Dinmore, and the different leaf stages present suggest that they represent colonies of young submerged plants, mats of floating leaves, or a mixed assemblage of both. The leaf material closely matches the range of variation evident in young sporophytes of Ceratopteris Brongn., but in the complete absence of Cenozoic fossils of the spore genus Magnastriatites Germeraad, Hopping & Muller emend. Dettmann & Clifford from mainland Australia, which are the fossil spores of this genus, it is referred to a new genus, Tecaropteris. The record of ceratopterid-like ferns adds significantly to our limited knowledge of Cenozoic freshwater plants from Australia. The geoheritage significance of sites, such as Dinmore, is discussed briefly. Andrew C. Rozefelds [andrew.rozefelds@qm.qld.gov.au], Queensland Museum GPO Box 3300, South Brisbane, 4101, Queensland, Australia and School of Earth Sciences, University of Queensland, St Lucia, 4072, Queensland, Australia; Mary Dettmann [mary.dettmann@qm.qld.gov.au], H. Trevor Clifford [trevor.clifford@qm.qld.gov.au] and Debra Lewis [debra.lewis@qm.qld.gov.au], Queensland Museum, GPO Box 3300, South Brisbane, 4101, Queensland, Australia.

Monocotyledon fruits and seeds, and an associated palynoflora from Eocene–Oligocene sediments of coastal central Queensland, Australia

Fruits of Restionaceae and seeds of Typhaceae are described from a latest Eocene-Oligocene mudstone underlying oil shales in a subsurface sequence near Rockhampton, coastal central Queensland. The Restionaceae fruits are unilocular and encase a single pendulous orthotropous seed with a structured micropylar cap, which may be tannin filled. These are allocated to Restiocarpum gen. nov., which has as its type Restiocarpum latericum sp. nov., and four other taxa described herein; Restiocarpum tesselatum sp. nov., Restiocarpum verrucatum sp. nov., Restiocarpum laeve sp. nov., and Restiocarpum fusiforme sp. nov. Typhaspermum cooksoniae gen. et sp. nov., which accommodates asymmetric claviform seeds, is interpreted as a member of the Typhaceae based on the presence of a lid-like operculum, bitegmic wall, and chalazal cavity.Reconstruction of the source plant community emphasizes similarities to restiad swamps of present day Wallum (swamp heathland) vegetation which is extensively developed along the Queensland coast. Biogeographic implications for the Restionaceae and Typhaceae are discussed.

Ultrastructure and biogeography of Balmeisporites Cookson and Dettmann, 1958

Abstract Ultrastructural and morphological analyses of Balmeisporites holodictyus reveal a two-layered wall conformable with that of spores of aquatic ferns. The spheroidal, trilete exospore comprises two zones with columnar structure sandwiched between homogeneous innermost and outermost zones. The outer wall layer, the epispore, has an inner reticulate-fibrillate zone and a homogeneous outer zone: the epispore forms the proximal tripartite acrolamella, prominent reticula in each equatorial radial region and surface sculpture. Ghoshispora shares with Balmeisporites wall ultrastructural and acrolamellate characters, but lacks protruding reticula in each equatorial radial region and possesses second order sculpturing of muri, striae or rugulae. The fossil record indicates that Balmeisporites originated in the Tethyan region during the Barremian-Aptian and for the remainder of the Cretaceous was concentrated in mid-high latitudes of both hemispheres. Ghoshispora had a shorter history with appearances in the Albian of Peru; during the Late Cretaceous its distribution range was centred in northern Laurasia, and, as reported herein, rare occurrences are in the Maastrichtian of Australia. Both genera are unknown in sediments younger than the Danian.

Feeding habits of the mahogany glider: Palynological evidence

Abstract Palynology has proven an effective method in providing supportive and new information on the visitation/foraging habits of the mahogany glider (Petaurus gracilis) in coastal northern Queensland, Australia. Pollen constitutes at least 30% by volume of the maceral contents in six of the eight fecal and intestinal samples examined. Pollen counts indicate that Myrtaceae taxa and Xanthorrhoea are the most frequently visited flowers, but significant occurrences of Banksia pollen suggest that it may also have been foraged. Incidental occurrences of Acacia, GrevilleaJ Hakea, Asteraceae, Casuarina, Deplanchea, and Ilex confirm the presence of these taxa within the gliders habitat.