Taxonomic and biogeographic insights into Australasian fingerworts in the Lepidozia ulothrix clade

The Australian and New Zealand floras exhibit a high degree of endemicity among bryophytes. The genus Lepidozia, commonly known as fingerworts and belonging to the Lepidoziaceae family, boasts more than 20 species, most of which are endemic to these countries. Although the genus has been extensively studied in New Zealand, debates persist regarding the precise delineation of species.

This study concentrated on the Lepidozia ulothrix clade, which comprises species present in both Australia and New Zealand. By conducting phylogenetic analyses on a multilocus dataset and applying various molecular species delimitation methods, the researchers found evidence supporting the conspecificity of L. serrulata and L. ulothrix.

This conclusion aligns with the morphological variations observed in Tasmanian and New Zealand populations. Additionally, the distribution of L. septemfida reaches the Wet Tropics Bioregion in north-east Queensland, where the species is characterized by a distinct subspecies rather than a separate species. The morphological disparities between Queensland and south-east Australian populations, combined with inconsistencies in species-delimitation results, justify the subdivision of the species into two subspecies.

Notably, Tasmanian and Victorian specimens previously classified as the New Zealand endemic L. hirta turn out to belong to a separate, unnamed lineage. This study underscores the potential of integrative taxonomic approaches in revealing hidden diversity and refining species circumscriptions, even within well-studied Australasian lineages like Lepidozia.