Landcare Research - Manaaki Whenua

Landcare-Research -Manaaki Whenua

Guide to New Zealand's freshwater invertebrates

Swimming mayfly ( Ameletopsidae : Ameletopsis )

Diagnostic features

Ameletopsis mayfly nymphs have a wide, skull-like head, and their caudal filaments (“tails”) are fringed on each side.

Typical habitats

Ameletopsis larvae are most abundant in bush-covered, gravelly streams with cool and well aerated water.


They are predators, feeding on other freshwater invertebrates.

Indicator value

Ameletopsis are not often found in high abundance, but they are indicative of good habitat and water quality, especially if other mayfly or stonefly groups are abundant. Ameletopsis has the highest tolerance value of 10 for both hard and soft bottom sites.