Landcare Research - Manaaki Whenua

Landcare-Research -Manaaki Whenua

Guide to New Zealand's freshwater invertebrates

Free-living caddis ( Polycentropodidae : Plectrocnemia )

Diagnostic features

Plectrocnemia caddis larvae have no mobile case, no chelae (pincers) and they have a speckled head pattern. There is a curved line of small dark spots running across the middle of the head.

Typical habitats

Plectrocnemia larvae are occasionally found in gravelly streams with slow to moderate current speeds throughout New Zealand.


They construct delicate filter-feeding nets to trap drifting particulate food items, possibly including other invertebrates and plant fragments.

Indicator value

Plectrocnemia larvae can be an indication of good water quality, particularly if they are found along with a range of mayfly and stonefly taxa. They have tolerance values of 8 (hard bottom sites) and 6.6 (soft bottom sites).