In recent years, an increase in baseline arthropod surveys and closer scrutiny of specimens from current and past collections have resulted in a rise of adventive psyllid species discoveries in the Hawaiian Islands. In some cases, the new records reported here may have been known for some time but not officially published in the literature. In other cases, specimens remained unidentified for several years. We provide an updated checklist of the 23 adventive psyllid species in the Hawaiian Islands, including six new state records, and at least one new island record. The majority of recent psyllid establishment records, including those newly reported here, are in the subfamily Spondyliaspidinae (Aphalaridae). These records are overwhelmingly Australasian in origin, with host plant associations in the family Myrtaceae, predominantly Eucalyptus. One of these new Australasian-origin records, Australopsylla exotica Matsunaga & Percy, sp. nov., is described here as a new species from adults and immatures. A molecular systematic overview of the phylogenetic placement of native and adventive taxa includes an analysis of the position of A. exotica within Australopsylla.