PALAEOBOTANICAL RESEARCH GROUP UNIVERSITY  MÜNSTER

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

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