Noeggerathians †

Historically the Noeggerathians have been classified as many different groups: cycads, equisetophytes, ferns, and progymnosperms. Well-preserved fossils from Inner Mongolia, China, indicate that they are a heterosporous group of progymnosperms. They were success and dominant in Permian swamps, but disappear during the Permian extinction event.

Ecology and Habit

  • Dominant in some Permian swamps

  • Some are interpreted as being small plants (e.g. Noeggerathia foliosa)

Stems

  • Gymnospermous wood

Leaves

  • Noeggerathia bears leafy shoots with two opposite rows of leaves

    • Leaves are obovate and obliquely attached to stems

  • Tingia, similar to Noeggerathia, with longer anisophyllous leaves born in four vertical rows (Kon'no & Asama 1951)

Reproduction

  • Spore-bearing plants

  • Two-ranked laminate sporophylls born at end of vegetative branches

    • Sporangia are attached adaxially

    • Slight heterospory is exhibited in sporangia (e.g. Noeggerathiaestrobus)

  • Bisporangiate cones with whorls of sporophylls (e.g. Discinites)

  • Tingiostachys are cones attached to the leaves of Tingia

    • Cones fork once at the base

    • Sporophylls are helically arranged and attached by a pedicel