Austrosimulium is a member of the simuliid blackfly (commonly called “sandfly”) family. They have small larvae characterised by a bulbous abdomen and a head bearing filter-feeding fans. The larvae use small hooks at the end of the abdomen to attach to submerged surfaces, while the filter-feeding fans are extended to face the current.
Austrosimulium larvae are found in fast and slow flowing, hard bottom and soft bottom streams in bush covered, farmland and urban areas.
Austrosimulium larvae are filter feeders using their fan of setae to collect drifting fine particulate organic matter.
Austrosimulium larvae can be abundant in pristine streams, but also in poor quality urban streams. They have low tolerance values of 3 (hard bottom sites) and 3.9 (soft bottom sites).