Diphasiastrum comprises some 20-30 species of similar morphology and/or great phenotypic plasticity.
The genus has a global distribution and some taxa are very widespread. However, their phylogenetic and biosystematic relationships remain unclear. Some studies claim evidence of widespread hybridisation, including homoploid hybrid speciation, but little evidence has been produced to support any such claims.
This genus is studied in collaboration with:
J Vogel