Morphological study on the Devonian zosterophyll Serrulacaulis Hueber and Banks: New materials and emendation

The generic diagnosis of the Mid–Late Devonian zosterophyll Serrulacaulis Hueber and Banks is emended based on morphological study on specimens from New York State (USA), Belgium and Venezuela, and new materials of S. spineus n. sp. from the Middle Devonian Hujiersite Formation of Xinjiang, Northwest China. The new species S. spineus has bilateral obdeltoid emergences and sparsely arranged spines on the axis surface, alternately arranged, reniform sporangia with unequal valves. A variety of the axial emergence appearances of Serrulacaulis is noted, which further indicates easily recognizable features of the genus.