Justicieae II: Resolved Placement of Many Genera and Recognition of a New Lineage Sister to Isoglossinae

We present phylogenetic results for Justicieae, the largest of major lineages Acanthaceae. With 300% more sequence data and a similarly increased but also geographically representative taxon sample compared to only previous study lineage as whole, we confirm existence Pseuderanthemum Lineage, Isoglossinae, Tetramerium Lineage Justicioid Lineage. To last three lineages, add number taxa with goal advancing our knowledge genera (e.g., Isoglossa, Rhinacanthus) geographic areas Malagasy Asian Acanthaceae). These added are accommodated within framework established in earlier work one exception. The monospecific genus Ichthyostoma is not placed any instead sister (Tetramerium + Lineage). As this result unexpected, examined topologies both including excluding plant which revealed that other aspects relationships remain stable whether included or not. point several Justicieae will benefit from additional study. One species Isoglossa all sampled members Isoglossinae. Pollen morphology I. variegata consistent its placement here than taxonomic assignment Isoglossa. suggested work, pollen can be powerful signal Justicieae. sampling, show Ptyssiglottis relatively small group African plants, warrants recognition separate addition now, related follows: (Pseuderanthemum ((Isoglossinae Lineage) Lineage))). has been understudied date attempt include representatives putatively part test monophyly larger genera. identify strongly supported clades some relationship unresolved. Asystasia, Graptophyllum, Oplonia, monophyletic although, nomenclatural changes, first second rendered monophyletic. range essentially extensive biogeographically complex patterns distribution suggestive multiple shifts between continents Australia parts Pacific basin. calibrated phylogeny confirms intercontinental across must have by long-distance dispersal rather vicariance stepwise over land bridges points groups potentially undergone rapid diversification. particular, requires considerable research understand achieve an informative taxonomy group. Although establish Next Generation Sequence necessary elucidate details most lineages. Additional structural characters warranted continue unable synapomorphies very molecular data.