Home     
 

Glossary | Information Sources | Terminology Images

Print This Page

 Major Groups | Insecta (insects) | Trichoptera (caddisflies) | Hydropsychidae
 

Hydropsychidae

Major Group: Insecta
Order: Trichoptera
Family: Hydropsychidae

Descriptive Features:

  • head capsule variable, upper surface can be convex or flattened, with or without a lateral carina
  • all 3 thoracic nota are sclerotised, the mesonotum and metanotum are without a medial ecdysial line
  • prosternum has a broad posterior sclerite
  • abdominal segments bear conspicuous branched ventral gills, usually there are also ventral gills on both the meso- and metathorax
  • abdominal segments 8 and 9 have a moderately large pair of ventral sclerites bearing a stout backward directed spine like setae
  • abdominal prolegs are strongly developed, each usually bearing a dense cluster of long setae near the apex, with a robust terminal anal claw
  • Total length: 5 - 25 mm

    • Taxonomic Checklist: Genera
    Aethaloptera
    Asmicridea
    Austropsyche
    Baliomorpha
    Cheumatopsyche
    Diemeniluma     (larva unknown)
    Diplectrona
    Macrostemum
    Smicrophylax

    Distribution: Australia wide

    Sensitivity Rating: SIGNAL grade 6. Larval populations thrive at sites impacted by moderate organic enrichment.

    Functional Feeding Group: filtering collectors

    Ecology: Instream habitat: Hydropsychid larval populations can be very large in many Australian lotic communities. Larvae are restricted to moderate or fast flowing waters, living on rocks, boulders or submerged logs.
    Feeding ecology: Larvae are omnivorous, and a capture net is used to filter food particles from the water column, including algae, organic particles and small invertebrates.
    Habit: Larvae construct fixed retreats, incorporating plant fragments and mineral particles, on the upper surface or side of stable substrata. A silken capture net is also constructed, which is suspended in the current near the upstream entrance to the retreat. Larvae obtain oxygen from the water through paired ventral gills on each abdominal segment. Their feeding method gives them the common name of ‘net spinning caddis’ but the conspicuous gills also give them a common name of ‘feather gill caddis’.
    Life history: The time taken to develop from egg to pupa is variable, ranging from two to three months to more than a year. The pupal chamber is dome-shaped, made from small stones and mineral particles, sometimes incorporating organic debris, and lined with silk.
     

    fixed retreats and capture nets
     

    hydropsychid larva with midge larvae
     

    hydropsychid larva with mayfly larva
     
    Information Sources: Dean 1999, Dean et al 2004
     More ›››  key to genera