Comments on the taxonomy and distribution of Eucolaspis Sharp and Atrichatus Sharp in New Zealand and description of E. kotatou sp. nov. (Coleoptera: Chrysomelidae, Eumolpinae)

The Eumolpinae (Coleoptera: Chrysomelidae) from New Zealand are poorly known in terms of species diversity and, logically, of any downstream understanding of species features, including species distribution or ecology. This is true even though some of the species have been recognised as agricultural pests and associated with economic losses in the country. In this work, I have analysed the diversity and distribution of two genera of Eumolpinae that had been the subject of a taxonomic revision in the 1950s, Atrichatus Sharp and Eucolaspis Sharp. My observations, based on relatively abundant material from three collections and newly collected specimens, generally agree with the conclusions of that work, identifying two species of Atrichatus and at least five of Eucolaspis. I provide a new taxonomic character, namely the description of the spermathecae of all the species, as well as refined distribution maps based on available collection data. One new species of Eucolaspis is described, E. kotatousp. nov., from Te Paki, near Cape Reinga (Northland). In addition, E. antennata Shaw, previously known from only two specimens without locality data, is reported from Rotorua (Bay of Plenty). Despite loose similarities, Atrichatus–mainly distributed in the north of the South Island–and Eucolaspis–broadly sympatric with Atrichatus, but more diverse and widely distributed in the North Island–should not be considered as close relatives based on an important diagnostic character for higher-level systematics of Eumolpinae, namely a dorsal groove on the pygidium, present in the former and lacking in the latter. http://www.zoobank.org/urn:lsid:zoobank.org:act:05CCCC7C-E8DE-41F3-B0D1-F2090D79754B