The Cycloneura Marshall group of genera in New Zealand (Diptera: Mycetophilidae: Leiini)

The Cycloneura group of genera, as it is here defined, represents a significant component of the Leiini (Diptera: Mycetophilidae) in New Zealand. The group includes little known genera, such as Cawthronia Tonnoir & Edwards, Cycloneura Marshall, Paracycloneura Tonnoir & Edwards, Paradoxa Marshall and Sigmoleia Tonnoir & Edwards, which are reviewed, as well as two new genera, Tonnwardsia gen. n. and Waipapamyia gen. n., which are described here. The prominent feature of Cycloneura-like leiines is the peculiar course of the hind wing veins, CuA2 and A1. Typically, A1 approaches the sinuous course of CuA2, or the two veins even join each other, thereby forming a closed posterior cubital cell. In New Zealand the Cycloneura group is more speciose than previously thought. New species described in this paper are: Paracycloneura inopinata sp. n., Sigmoleia peterjohnsi sp. n., Sigmoleia separata sp. n., Sigmoleiasimilis sp. n., Waipapamyia dentata sp. n., Waipapamyia elongata sp. n., and Waipapamyia truncata sp. n. The New Zealand members of the Cycloneura group do not form a monophyletic group in themselves, but are variously related to extralimital taxa the majority of which is found in the southern Neotropics, South Africa, Australia, and New Caledonia. Possible relationships, with supporting arguments from adult morphology, are discussed.