Re-examination of specimens attributed to Sawdonia curstipa Wang and Hao (zosterophyll) from the Middle Devonian of Xinjiang, China

Specimens previously attributed to Sawdonia curstipa were re-examined. Some of the specimens are transferred to Serrulacaulis cf. S. furcatus based on axial morphology. Other specimens, including fertile axes with one or two rows of sporangia with curved stalks and sterile axes with cone-shaped spines covering the surface, are of uncertain assignment due to poor preservation. The nomenclature problem of Sawdonia custipa is also noted.