Discinida is an order of comprising the extant superfamily Discinoidea, and the extinct superfamilies Botsfordioidea (early—mid-Cambrian) and Acrotheloidea (early Cambrian–Early Ordovician). It represents a sister taxon to the Lingulida, and is possibly paraphyletic with respect to the Acrotretida.—or the acrotretids are paraphyletic with respect to it.> The group displays a broad range of shell structures, some of which incorporate substantial organic or silicified components.
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