Systematic revision of the Mayfly genus Deleatidium Eaton (Leptophlebiidae)

Abstract

The systematic position of the mayfly genus Deleatidium Eaton is reviewed, and the relationships of the 6 New Zealand species elucidated by a redescription of the adult characters and an examination of the larval characters not previously described. Two new species are described. The subgenus Atalophlebioides Phillips is redefined and divided into two groups. A short account of the ecology of the genus is included. Three factors; oxygen content of the stream-water, rate of flow, and availability of diatoms as food limit the distribution of these species in New Zealand.