Dapingian first appearances

The embryophytes () are plants of the clade Embryophyta, also known as 'Plantae sensu strictissimo (, "plant in the strictest sense") or land plants'. They are complex multicellular eukaryotes with haplodiplontic life cycles, all have specialized reproductive organs called sporangia, and reproduce sexually via alternation of generations using spores or seeds. The name "embryophyte" derives from their innovative characteristic of nurturing the embryonic sporophytes within the tissues of the parent gametophytes during the early stages of multicellular development. They are the dominant group of

Aulacopleura is a genus of proetid trilobite that lived from the Middle Ordovician to the Middle Devonian. Some authors may classify this group as subgenus Otarion (Aulacopleura). The cephalon is semicircular or semielliptical, with border and preglabellar field. The glabella is short, with or without defined eye ridges connecting it with eyes of variable size. Spines at the rear outer corners of the cephalon (or genal spines) are present, typically reaching back to the 2nd to 4th thorax segment. The 'palate' (or hypostome) is not connected to the dorsal shield of the cephalon (or natant). The