Photomicrograph gallery of species of Reduviasporonites - Abstract

Description and illustration of species of the genus Reduviasporonites
(Wilson 1962)
Dr M H Stephenson, British Geological Survey, Keyworth, Nottingham, UK.
Prof C B Foster, Geoscience Australia, Canberra ACT, Australia

A 'spike' of supposed fungal spores occurs at the Permian–Triassic boundary in various locations, in close association with a mass extinction event (Erwin, 1993). This close relationship has lead palynologists (Eshet et al., 1995; Visscher et al.; 1996, Elsik, 1999) to consider that the supposed fungus may have been a saprophytic metaboliser of dead vegetation formed during the extinction event. Elsik recently (1999) suggested that two of the taxa often associated with the 'fungal spike': ChordecystiaFoster 1979 from the Australian Rewan Formation, and Tympanicysta Balme 1980 from the Martinia Shale, Greenland, are junior synonyms of Reduviasporonites Wilson 1962, and affirmed a fungal origin for the latter. It is not clear if topotype material was re-examined to support this conclusion. In contrast Krassilov et al. (1999) suggested that 'spores' assigned by Russian palynologists to Tympanicysta are more closely allied to the zygnemataceaen algae.

For this study, we have examined topotype material of Reduviasporonites chalastus (Foster) Elsik 1999 and Reduviasporonites catenulatus Wilson 1962, as well as well-preserved specimens of these taxa from Greenland, Britain, China, Saudi Arabia, Russia, Australia and Austria, to allow comparative study.

The aims of the project were to:

  • describe and illustrate the detailed morphology of Chordecystia Foster 1979, Tympanicysta Balme 1980 and Reduviasporonites Wilson 1962
  • determine whether the taxa are synonymous
  • determine whether the taxa have fungal or algal origins.

Use the links in the menu for further information and to go to the galleries.