Pseudosporochnales †

Diversity

Calamophyton †

• Kräusel & Weyland, 1929; Giesen & Berry, 2013

• Middle Devonian 

C. primaevum †

• • Originally described from the Middle Devonian of Germany

  • Eifelian specimens from Somerset, England, are currently the earliest known tree-like plants (~390 Ma)

  • Calamophyton primaevum branches have been demonstrated to be attached to the distal end of Duisbergia mirabilis trunks (Giesen & Berry, 2013)

  • 35 cm long plant reconstructed with a finger-like branched main axis

  • The short, dichotomously branched axes bear a single sporangium at each end of each axis

  • In cross-section, stems exhibit a variable number of xylem lobes, ranging from 10 to 33

    • In the distal parts of the plant, there were fewer xylem lobes

    • The xylem strands are extended radially in the cross-section

  • Ground tissue of stem exhibits fiber bundles

C. bicephalum †

• • Leclercq and Andrews, 1960

  • Middle Devonian 

  • Central axis with finger-like arranged side branches with a diameter of about 1 cm and branch dichotomously

  • In cross-section, the axis has 14 to 16 xylem segments, which are either oval or have 4-5 radial arms

    • There is only primary xylem

  • The "leaves" are three-dimensional structures, each divided dichotomously once horizontally and once vertically

  • Young leaves in the distal region of the plant bifurcate only once; axes in the lower area divide up to four times

  • There are indications that leaves and sporangia have been on different axes

  • The fertile axes are inserted in a pseudowhorl arrangement; sometimes fertile axes are interspersed between sterile whorls

Eospermatopteris †

• Goldring, 1924; Stein et al. 2007

• Givetian of New York, Belgium, Germany

• Large bulbous trunk casts; most do not preserve the aerial portions, but indicate a tree-sized plant for this time

• Carbonaceous strands in the trunk represent poorly preserved vascular strands that exhibit complex anastomoses

E. eriana †

• Goldring 1924; Boyer, 1995; Stein et al. 2007

• Givetian of Gilboa, NY

• One of the oldest known tree-like plants

• Aerial portions most probably Wattieza (see below)

E. textilis †

• Goldring 1924; Boyer, 1995

• Combined with E. eriana (Boyer, 1995)

Pseudosporochnus †

• Potonié & Bernard, 1903

• Middle-Late Devonian (Frasnian)

• Small tree (2-4 meters tall) with a bulbous base

• Lateral axes dichotomized several times dichotomous

• The terminal branches are three-dimensional

• Sterile and fertile units are similar, with the latter possessing paired ellipsoidal sporangia

P. hueberi 

• • Stein & Hueber, 1989

  • Originally named Cladoxylon hueberi

  • 40-50 xylem strands in the main axis and 20-25 in the lateral axes

  • Only primary xylem is present and metaxylem tracheids possess uni- to multiseriate bordered pits

P. nodosus 

• • Leclercq and Banks, 1962

  • Second-order branches dichotomized with the lateral branching system giving rise to ultimate branching units that are three-dimensional

  • Fertile branching units possess sessile, ellipsoidal sporangia

  • Circular–elongate structures distributed on all parts representing nests of cortical fibers