Landcare Research - Manaaki Whenua

Landcare-Research -Manaaki Whenua

Guide to New Zealand's freshwater invertebrates

Free-living caddis ( Polycentropodidae : Polyplectropus )


Diagnostic features

Polyplectropus caddis larvae have no mobile case, no chelae (pincers) and they have a distinctly speckled head pattern. The head pattern does not include a curved line of spots (the related Plectrocnemia has a curved line of spots across the head).

Typical habitats

Polyplectropus larvae are common in slow-flowing gravelly streams, or soft bottom streams with woody debris, throughout New Zealand.

Feeding

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

Indicator value

Polyplectropus larvae are most common in streams of moderate to good quality, as reflected by their tolerance values of 8 (hard bottom sites) and 8.1 (soft bottom sites).