The diversity of Clavariadelphus species in oak-hornbeam dominated forests of the Czech Republic was clarified using DNA sequences of the ITS region of the ribosomal RNA gene. We report four species from the habitat: C. flavoimmaturus, C. griseoclavus, C. pistillaris, and C. xanthocephalus. A generally poor match between identification based on morphological characters and ITS sequences was observed, which questions the validity of morphological characters used in identification keys. Clavariadelphus griseoclavus is newly reported in Europe and its possible conspecifity with the older species C. helveticus is discussed. The recently described East Asian species C. khinganensis is likely to be conspecific with C. xanthocephalus.
Tomšovský M., Zíbarová L., Soják M., Tejklová T., Kříž M. (2026): Clavariadelphus flavoimmaturus, C. griseoclavus, and C. xanthocephalus in oak-hornbeam forests in the Czech Republic. – Czech Mycology 78(1): 39–57.
