While building a new tool to browse GBIF data I ran into a problem that the taxon "Jungermanniales" popped up in two different places in the GBIF classification, which broke a graphical display widget I was using.
If you search GBIF for Jungermanniales you get two results, both listed as "accepted":
Plantae > Marchantiophyta > Jungermanniopsida
Plantae > Bryophyta > Jungermanniopsida
Based on Wikipedia pages for Marchantiophyta, traditionally liverworts such as the Jungermanniales were included in the Bryophyta, but are now placed in the Marchantiophyta. The GBIF classification has both the old and the new placement for liverworts (sigh).
As an aside, I couldn't figure out why Wikipedia gave the following as the reference for the publication of the name "Marchantiophyta":
Stotler, R., & Crandall-Stotler, B. (1977). A Checklist of the Liverworts and Hornworts of North America. The Bryologist. JSTOR. doi:10.2307/3242017
This paper doesn't mention "Marchantiophyta" anywhere. The other authority Wikipedia gives is:
Crandall-Stotler, B., Stotler, R. E., Long, D. G., & Goffinet, B. (2001). Morphology and classification of the Marchantiophyta. (A. J. Shaw, Ed.)Bryophyte Biology. Cambridge University Press. doi:10.1017/cbo9780511754807.002
which is behind a paywall that my University doesn't subscribe too. However, the following reference
Stotler, R., & Crandall-Stotler, B. (2008). Correct Author Citations for Some Upper Rank Names of Liverworts (Marchantiophyta). Taxon, 57(1):289-292. jstor:25065970
Marchantiophyta was validly published (Crandall Stotler & Stotler, 2000) by reference to the Latin description of Hepatophyta in Stotler & Crandall-Stotler (1977:425), a designation formed from an illegitimate generic name, Hepatica Adans. non Mill, and hence not validly published under Article 16.1, cross-referenced in Article 32.1(c) of the ICBN (McNeill & al, 2006). Marchantiophyta phylum nov. is redundant in Doweld (2001) who established a later isonym by likewise citing the Latin description in Stotler & Crandall-Stotler (1977) for his proposed "new name."
And who said taxonomy couldn't be fun?