Landcare Research - Manaaki Whenua

Landcare-Research -Manaaki Whenua

Guide to New Zealand's freshwater invertebrates

Swimming mayfly ( Siphlaenigmatidae : Siphlaenigma )

Diagnostic features

Siphlaenigma mayfly nymphs have a torpedo-like body form, and look like small delicate Nesameletus, but unlike Nesameletus they have antennae that are much longer than the head.

Typical habitats

Siphlaenigma larvae are infrequently recorded, but they have been found amongst submerged vegetation in slow flowing, bush covered streams.


We suspect the larvae feed on algae or decomposing plant matter on the streambed.

Indicator value

Siphlaenigma are most likely to be found in streams with good habitat and water quality. They have the high tolerance value of 9 for hard bottom sites (there is no tolerance value for soft bottom sites).