Systematics and biogeography of the New Zealand endemic genus Zorion Pascoe 1867 (Coleoptera: Cerambycidae: Cerambycinae), with descriptions of six new species : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Science in Zoology at Massey university
The genus Zorion (Coleoptera: Cerambycidae: Cerambycinae) commonly known as longhorn flower beetle is endemic to New Zealand and its species are distributed widely on the main and on some offshore islands. A taxonomic revision of Zorion is given, including thorough description including illustration of the genus. The previously known species Z. minutum, Z. guttigerum, Z. opacum, and Z. batesi are redescribed, Z. castum is synonymised with Z. guttigerum, and Z. angustifasciatum, Z. australe, Z. dugdalei, Z. kaikouraiensis, Z. nonmaculatum and Z. taranakiensis are described as new species. A key to all ten species is provided. Z. exiguum has been excluded from the study because the original description and the holotype could not be located. The beetles are pollen feeders and visit a variety of plant species for feeding, mating and oviposition. The phylogenetic relationship of all ten species was analysed cladistically using PAUP. Results show that Z. taranakiensis is the sister taxon to the unresolved clade of Z. batesi, Z. angustifasciatum and Z. dugdalei. Z. australe and Z. nonmaculatum, whose relationship remains unresolved form a sister group to the Z. taranakiensis group. Z. guttigerum and Z. kaikouraiensis are sister taxa forming a sister group to the Z. australe group. Z. minutum is the sister taxon to the latter eight species and Z. opacum the sister taxon to all species in this study. The relationships between Zorion species reflect their distribution patterns, which are discussed in relation to New Zealand's biogeographical history.