Pleuromeiales †

Mesozoic clubmoss with cormose base

Ecology & Form

Stems

  • Herbaceous or pseudoherbaceous

Morphology

  • Upright and unbranched; 30 cm long and 2-3 cm wide in the earliest species to around 2 m long in later species

Anatomy

  • Lacks secondary tissues

Leaves

  • Lycophylls or microphylls are long and grass-like

  • Helically arranged

Roots

  • Lobed, cormose with stigmarian-type appendages

Reproduction

  • Terminal cones with sporangia

    • Sporangia on adaxial (top) surface

  • Homosporous and heterosporous forms

Classification

└Embryophytes

└Polysporangiophytes

└Tracheophytes

└Eutracheophytes

└Lycophytes

└Lycopsida

└Pleuromeiales †

Geologic Range

Diversity

  • Pleuromeia †

  • Cylostrobus †

  • Ferganodendron †

  • Lycostrobus †

  • Nathorstiana †