Abstract

Bed TB33, a lacustrine unit within the late Eocene (early Priabonian) How Ledge Limestone, Headon Hill, Isle of Wight, UK, contains a rich mammalian fauna. The previously reconstructed food web included mammalian predators and prey (ground dwelling, scansorial and arboreal; insectivores, frugivores, herbivores and carnivores) and two inferred owls. Unfortunately, the extensive bulk sediment sampling and sieving used to obtain the vertebrate fauna had not yielded any plant fossils other than charophyte gyrogonites. This new work has focused on plant mesofossils and palynofacies in the uppermost horizons of the vertebrate-rich bed aiming to reconstruct the vegetation that hosted the mammals. Other than cysts of Zygnemataceae, phytoplankton are absent. The presence of the aquatic plants Azolla and Salvinia on the lake is documented by megaspores and microspore massulae. The palynomorphs are dominated by algal cysts, Azolla microspore massulae fragments and two morphologies of trilete fern spores. These data document a depositional setting in a lake with abundant free-floating Azolla or Salvinia and with a margin vegetation dominated by ferns. The data support one of our previous inferences that the arboreal mammals were brought to the site from some distance away by predators. However, the challenge to fully reconstruct the mammalian habitats remains.

Key words

Eocene, mammal, primate, plant mesofossils, resin, algal cyst, pollen, spore, seed, megaspore, microspore massulae, Azolla, Salvinia

Abstract

Following on the seminal works of Reid and Chandler in 1933 and Chandler in 1961, morphology and anatomy of fossil mastixioid fruits from the early Eocene London Clay of southern England were reanalyzed with the benefit of new methods in comparison with extant genera of Mastixiaceae and with other fossil representatives from Europe and North America. The species named Mastixia cantiensis E.Reid et M.Chandler was based on a heterogeneous assemblage of specimens, all representing Mastixiaceae, some of which truly represent Mastixia whilst others correspond to Diplopanax and Mastixiopsis The holotype of M. cantiensis E.Reid et M.Chandler corresponds to extant Diplopanax rather than Mastixia. Therefore, this species is moved out of Mastixia and is treated as Diplopanax cacaoides (Zenker) comb. nov. Nine species of mastixioid fruits are currently recognized in the London Clay flora: Mastixia parva E.Reid et M.Chandler, M. cf. oregonensis (R.A.Scott) Tiffney et Haggard, Diplopanax cacaoides, Tectocarya grandis (E.Reid et M.Chandler) comb. nov., Mastixiopsis nyssoides Kirchh., Exbeckettia mastixioides (E.Reid et M.Chandler) gen. et comb. nov., Lanfrancia subglobosa E.Reid et M.Chandler, Portnallia bognorensis M.Chandler, and Langtonia bisulcata E.Reid et M.Chandler. These include the oldest known representatives of the genera Diplopanax, Tectocarya and Mastixiopsis and contribute to our understanding of the former morphological diversity and palaeobiogeography of the Mastixiaceae.

Key words

Beckettia, biogeography, Diplopanax, Exbeckettia, Lanfrancia, Langtonia, Mastixia cantiensis, Mastixiaceae, Mastixiopsis, Portnallia, taxonomy, Tectocarya grandis

Abstract

The late Early/early Middle Miocene flora from Parschlug (Styria, Austria) is famous for its numerous specimens and high diversity. Some taxa previously described are revised here and 42 new angiosperm leaf morphotypes/taxa are described. The Climate Leaf Analysis Multivariate Program (CLAMP) is applied to assess the palaeoclimate. An update of the tool to assess the most suitable modern climate CLAMP calibration dataset is introduced. The Integrated Plant Record (IPR) vegetation analysis, assessing the most likely major vegetation type represented by a fossil flora, and similarity approaches Drudges 1 and 2, indicating the most similar modern vegetation proxies, had been previously applied to data from Parschlug. Both are again applied here on the enlarged floristic spectrum. The results indicate “sclerophyllous subhumid forest” as the most likely major zonal vegetation type for Parschlug and European vegetation, namely “Thermophilous mixed deciduous broadleaved forests”, distributed today in southern and southeastern Europe, as the most similar modern vegetation. The climate for Parschlug, inferred from CLAMP and the climate in the region of the modern vegetation proxies, indicates distinct seasonality in precipitation and temperature.

Key words

leaf flora, CLAMP, IPR vegetation analysis, Drudges, modern vegetation and palaeoclimate proxies, Neogene, Austria