A new sphenopsid cone from Iowa

A new Pennsylvanian cone genus (Litostrobus iowensis, n. gen., n. sp.), apparently of sphenophyllalean affinity, is described on the basis of a coal-ball specimen from the Urbandale Mine, Urbandale, Iowa. The cone is small and extremely simple in organization. It consists of superposed whorls of twelve bracts each. The bases of the bracts are fused to form shallow cuplike discs. Six sporangia are produced in each whorl; they are erect, each terminating a short, thick, axillary pedicel. Small spores with highly distinctive ornamentation are present in the sporangia.Comparison with other previously described sphenopsid fructifications reveals morphological differences that warrant recognition of the Urbandale specimen as a new genus.