Vanuatubasis Ober and Staniczek is a genus of damselfly endemic to Vanuatu. Little is known about the distribution and general natural history of the genus. We present the results of 14 weeks of fieldwork in Vanuatu to provide a better understanding of the biology of this genus. Specifically, we tested ecological niche models to predict the presence of Vanuatubasis throughout the region and explored how water pH may play a role in their distribution and ecology. The results of this fieldwork refined our model and further predicted the presence of this genus on additional islands. We also found stream pH as a strong predictor for the presence of Vanuatubasis, with their presence in alkaline streams significantly higher (p < 0.001). The mean pH for those streams where the genus was collected was 8.44 (n = 53).

The genus Anax is a group of cosmopolitan dragonflies noted for its conspicuous migratory behaviours and large size. Here we present the first dated, species-level, multigene, molecular phylogeny for the group to test generic and species-limits, as well as the evolution of migration and range size. Using five mitochondrial and nuclear gene regions (COI, COI/COII, CYTB/ND1, ITS1 and PRMT) from 20 species, we reconstructed a phylogeny of Anax using both a Bayesian and maximum likelihood approach. We found that Anax (including its hypothesized sister group Hemianax) forms a monophyletic group, and that 12 out of 20 species tested positive for monophyly were also monophyletic. The monophyly of several species of Anax is less clear. Migratory behaviour, which is known to occur in at least nine species, is recovered as the ancestral behaviour, which was lost and subsequently gained at least three times. Geographic range size seems to be tightly associated with migratory behaviour.

The monotypic genus Oficanthon Paulian, 1985 (Coleoptera: Scarabaeidae: Scarabaeinae) is treated as a junior synonym of the genus Lepanus Balthasar, 1966, and L. mirabilis (Paulian, 1985), new combination is proposed for Oficanthon mirabilis Paulian, 1985. Both morphological and molecular evidence support this synonymy. Morphological evidence further supports its placement within the Lepanus ustulatus species group. Lepanus mirabilis is redescribed.

Additional work on the islands of Vanuatu has improved our understanding of the actual diversity of South Pacific coastal fireflies. Prior to recent fieldwork in Vanuatu, the only known lampyrid from Vanuatu was Atyphella aphrogeneia (Ballantyne), a coastal species also found in Papua New Guinea. After further examination, we determined that specimens from Vanuatu formerly classified as Atyphella aphrogeneia actually belong to an undescribed species. New species, Atyphella maritimus Saxton and Powell and Atyphella marigenous Saxton and Bybee, are described from specimens collected in Vanuatu. An updated key for coastal Atyphella in the South Pacific is provided.