nomenclatorial act:
protologue/first publication
Page:
639
diagnosis:
Coniferophytic seed plants with compound ovulate fertile zones and simple pollen cones; branched, woody stems bearing closely spaced simple and forked leaves. Stems eustelic with enarch primary xylem, dense wood; leaves vascularized by single bundle, stomata in two adaxial bands, guard cells with papillate subsidiary cells; stomatoliferous grooves absent. Pollen cones simple, pollen sacs borne adaxially on sporophylls, producing monosaccate, eusaccate prepollen. Ovuliferous dwarf shoots in axils of helically arranged bracts, radial with numerous vegetative scales; sporophylls erect; ovules with thick megaspore membrane.
systematic position:
Spermatopsida, Order Indet.
typeseries:
Barthelia Rothwell & Mapes, 2001
Classification:
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