P. pyramidalis is one of two psyllids causing conical galls on Ohia and one of more than a dozen Pariaconus psyllids that cause a variety of galls on the plant. For a description of these galls, see Percy DM (2017) Making the most of your host: the Metrosideros-feeding psyllids (Hemiptera, Psylloidea) of the Hawaiian Islands. ZooKeys 649: 1–163. https://doi.org/10.3897/zookeys.649.10213. For images of the galls, see pages 144-150. For P. pyramidalis gall images, see Figure 52-S to -W on page 150.