Cyrtomium lacrimipinnum Yoneoka, T. Fujiw., V. S. Dang & Tagane 2026, sp. nov.

A new species of fern, Cyrtomium lacrimipinnum, has been discovered in Phong Nha-Ke Bang National Park and Hin Nam No National Park, Vietnam. This species is distinguished by its teardrop-shaped lateral pinnae, black or dark brown microscales on both surfaces of the pinnae, and unique venation patterns. It closely resembles Cyrtomium pachyphyllum and C. hemionitis but differs in key morphological traits such as pinnae apex shape and margin characteristics. The discovery was made through herbarium surveys and fieldwork, with specimens collected from limestone outcrops and crevices within shrubby moist forests. Notably, this species is believed to reproduce sexually, a rare trait among Cyrtomium ferns, which are predominantly apogamous. Further cytological studies are planned to clarify its biological characteristics.

Yoneoka, K., Fujiwara, T., Dang, V.-S., Pham, Q. T., Souladeth, P., Sengthong, A., Masuda, R., Yamamoto, T., Tanaka, N., & Tagane, S. (2026). Cyrtomium lacrimipinnum Yoneoka, T. Fujiw., V. S. Dang & Tagane 2026, sp. nov. Zenodo. https://doi.org/10.5281/ZENODO.20493464