Voltziales

Walchia piniformis

The Voltziales are a group of extinct seed plants. They are considered the ancestors of the extant conifers.

  • 3.1 Notes and references

Features

The Voltziales are a rather heterogeneous group. In the past, a distinction was made between "volt social " conifers and " walchialen " conifers. The former are characterized by orthotropic branching, broad leaves, and short shoots with flattened, partially fused scales. The latter are branched plagiotrop, have needle-shaped leaves and short shoots bear radially arranged scales. The stomata form bands, the pollen is monosaccat.

System

Families

The two groups of "volt social " and " walchialen " Conifers are not clearly demarcated from each other and groups are now placed together in the order Voltziales. According to Taylor et al. (2009) include the following families to order:

  • Utrechtiaceae
  • Thucydiaceae
  • Emporiaceae
  • Majonicaceae
  • Ullmanniaceae
  • Bartheliaceae
  • Ferugliocladaceae
  • Buriadiaceae

The phylogenetic relationships of the different families of the two orders were reconstructed by Farjon as follows:

Thucydiaceae

Emporiaceae

Ullmanniaceae

Utrechtiaceae

Majonicaceae

Voltziaceae

Podocarpaceae

Phyllocladaceae

Araucariaceae

Pararaucariaceae

Pinaceae

Cephalotaxaceae

Taxaceae

Palissyaceae

Geinitziaceae

Doliostrobaceae

Cupressaceae

Sciadopityaceae

Cheirolepidiaceae

Ferugliocladaceae

Genera incertae sedis

Some species that are not adequately known, are from Taylor et al. (2009 ) none of the families assigned ( incertae sedis ), since not even considered their assignment to the Voltziales assured. They are:

  • Glyptolepis
  • Conewagia
  • Voltziopsis
  • Florinostrobus
  • Tricanolepis
  • Swedenborgia
  • Aethophyllum

Documents

  • Thomas N. Taylor, Edith L. Taylor, Michael Krings: Paleobotany. The Biology and Evolution of Fossil Plants. Second Edition, Academic Press 2009, pp. 807ff. , ISBN 978-0-12-373972-8
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