PALAEOBOTANICAL RESEARCH GROUP
UNIVERSITY  MÜNSTER


HISTORY  OF PALAEOZOIC  FORESTS
FOSSIL  FERNS


Ferns were widespread in the Carboniferous and Permian.  Many had a tree-like growth habit like modern tropical tree ferns.  However, though superficially looking very similar, modern tree ferns are not directly related to Palaeozoic forms.  The classification of fossil ferns is very difficult and many aspects are still uncleared.  Several classification schemes have been published.  A major problem is the often fragmentary nature of the material.  Some groups are exclusively based on anatomically preserved axes, whereas foliage and fructifications are still unknown.  Another problem is that the systematics of ferns is largely based on modern representatives and Palaeozoic forms often do not fit well is this very tight scheme.

Most groups of Palaeozoic ferns are extinct.  The Marattiales and the Osmundales are the oldest still existing fern groups and date back to the Late Carboniferous respectively Permian. It should be realised that the vast majority of extant ferns belongs to groups that have evolved in the Mesozoic.  The Polypodiaceae, the most succesful fern group today, is even much younger and dates from the Late Cretaceous our Tertiary.

Palaeozoic ferns had various growth strategies ranging from tree-like, to winding, climbing and epiphytic forms.  Together with the pteridosperms they probably formed a closed canopy below the upper, rather open canopy of arborescent lycopod trees.  After the extinction of most arborescent lycopods in the latest Westphalian, tree ferns became the dominant group of plants.  North American Stephanian coals may consist of up to 75% of tree fern remains. Keeping this in mind, it is remarkable that illustrations of fossil ferns are rather scarce on the internet.

Sometimes it is very difficult to distinguish true fern foliage from seed fern foliage; especially when fructifications are still unknown. In such cases fern(-like) foliage is accommotated in the informal category pteridophylls.


Taxon / Subject
Web Source
Comments
Pics
Info
Psaronius is a genus for anatomically preserved tree fern stems of Late Carboniferous-Permian Marattiales.  Late Palaeozoic Marattiales were real tree ferns unlike the modern representatives of this group. Psaronius stems typically have a well-developed root mantle which gives them stability. Foliage of Psaronius is of the Pecopteris type; Scolecopteris is a typical fertile form. This was one of the most common, widespread and diverse groups of ferns during the latest Carboniferous.  They prefered humid habitats and were part of peat-forming communities.
Psaronius Virtual Paleobotany Laboratory  
Psaronius Virtual Paleobotany Laboratory  root mantle
Psaronius K. Pigg's "Plant Fossils and Evolution"  
Psaronius K. Pigg's "Plant Fossils and Evolution" cross sections
Psaronius Ulrich Dernbach  
Psaronius roots Ohio State Univ. Lima  
Psaronius hexagonus ? click on image to enlarge
Psaronius melanedrus Paläobotanik Münster  
have a look!
Tietea singularis Ulrich Dernbach a tree fern stem from Brazil
Pecopterisand the genera Asterotheca, Scolecopteris established for fertile material
Pecopteris sp. Illinois State Mus., Mazon Creek Fossils  
Pecopteris Virtual Paleobotany Laboratory  
Pecopteris Virtual Paleobotany Laboratory  
Pecopteris arborescens Southern Illinois Univ. Museum  
Pecopteris mazoniana Southern Illinois Univ. Museum  
Pecopteris mazoniana Southern Illinois Univ. Museum  
Pecopteris mazoniana Southern Illinois Univ. Museum  
Pecopteris miltonii M. Hieb's Plant Fossils of W. Virginia  
Pecopteris plumosa Geol. Dienst NRW Krefeld  
Pecopteris arborescens SOES Collection  
Pecopteris arborescens Fossil Guy  
Pecopteris sp. Hans Steur's Paleobotany Pages   
Pecopteris M. Hieb's Plant Fossils of W. Virginia  
Pecopteris M. Hieb's Plant Fossils of W. Virginia  
Pecopteris M. Hieb's Plant Fossils of W. Virginia  
Pecopteris M. Hieb's Plant Fossils of W. Virginia  
Pecopteris Virtual Paleobotany Laboratory coal ball
Pecopteris Emporia State University  
Pecopteris SOES Collection  
P. (Senftenbergia) plumosa Westphalian D of Zwickau  
Asterotheca sp. Illinois State Mus., Mazon Creek Fossils  
Scolecopteris Ohio State University Lima coal ball 
Scolecopteris (P.) mertensiodes Westphalian D of Zwickau type specimen
Ptychocarpus (P.) unita Westphalian D of Zwickau identification probably incorrect
 
Several other groups of ferns and fern-like plants have been described from Palaeozoic rocks.  These include the fern-like Cladoxylales, the Zygopteridales (Coenopteridales) and true ferns like the Botryopteridaceae and Anachoropteridaceae.  Because their classification the systematics are still being discussed, they are here placed in a single category; where possible affinities are indicated under comments. 
Alloiopteris coralloides M. Hieb's Plant Fossils of W. Virginia Zygopteridales
Alloiopteris coralloides M. Hieb's Plant Fossils of W. Virginia  
Alloiopteris  coralloides Westphalian D of Zwickau listed as Saccopteris
Anachoropteris involuta Paläobotanik Münster coal ball - Anachoropteridaceae
have a look !
Ankyropteris K. Pigg's "Plant Fossils and Evolution"  coal ball - Tedeleaceae
Botryopteris Ohio State University Lima coal ball - Botryopteridaceae
Etapteris Virtual Paleobotany Laboratory coal ball - Zygopteridales
Oligocarpia gutbieri Westphalian D of Zwickau  
Pseudosporochnus Virtual Paleobotany Laboratory Cladoxylales
Saccopteris cristata Westphalian D of Zwickau Zygopteridales (Alloiopteris)
Stauropteris Virtual Paleobotany Laboratory coal ball - Stauropteridales
Guairea carnieri Ancient microworlds Osmundaceae - Permian
 
  =  excellent !   =  very good
  =  good
  =  fair
  =  poor / no information
 
Disclaimer

The last check of the list of links was done on 2 December 2002. The links give the most direct connections to pictures available on the web; in many cases they are from sites that have additional palaeobotanical information.  The above ratings refer to: 
1. Pics: the quality of the specimens, particularly with regard to characteristic features, and to the quality of the pictures. 
2. Info: the additional information provided; if applicable te general information on the main pages has been condered.
Ratings are of course subjective but should be helpful for finding the fastest way to good pictures on the web. Own pictures are of course not rated. This is up to you! 
Suggestions for improvement and hints to other internet resources are most welcome

 

© Forschungsstelle für Paläobotanik, Westfälische Wilhelms-Universität Münster
December  2002