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 Major Groups | Insecta (insects) | Ephemeroptera (mayflies) | Baetidae


Major Group: Insecta
Order: Ephemeroptera
Family: Baetidae

Descriptive Features:

  • head hypognathous, except for Platybaetis which has a prognathous head
  • antennae longer than width of head, usually as long as head and thorax combined
  • body streamlined with mottled colourings
  • thorax usually strongly humped, oval to circular in cross-section, except Platybaetis which is dorsoventrally flattened
  • hind wing pads present or absent
  • abdomen without posterolateral spines
  • plate-like gills on abdominal segments 1-7 or 2-7
  • inner margins of caudal filaments fringed with setae, except Platybaetis
  • Total length: up to 1O mm
  • Taxonomic Checklist: Genera
    (syn. Edmundsiops)

    Distribution: Australia wide

    Sensitivity Rating: SIGNAL grade 5. A species of Cloeon has been recorded from a wetlands with low nutrient levels.

    Functional Feeding Group: scrapers, gathering collectors 

    Ecology: Instream habitat: Baetid nymphs occur in almost all freshwater habitats, including the fast flowing riffle zone of rivers to the slackwaters of rivers, wetlands, billabongs and farm dams, but they are most diverse in cool, flowing waters. The nymphs are usually found near or on aquatic macrophytes.
    Feeding ecology:Baetid nymphs scrape algae and fine detritus from submerged rocks, wood and macrophytes.
    Habit: Nymphs are strong swimmers and move with a rapid up and down motion of their abdomen.
    Life history: Different species emerge at different times of the year, from August to May, and so there can be several generations of baetid nymphs living in the water simultaneously. Cloeon fluviatile, occurring in seasonal creeks in Northern Territory, has eggs that can withstand drying then develop rapidly in four weeks when innundated.

    immature without wing pads 

    Key Note: Specimens without wing pads are early instars and cannot be confidently identified at genus level.

    Information Sources: Suter 1997, Webb & Suter 2011, Dean & Suter 1996, Peters & Campbell 1991, Gooderham & Tsyrlin 2002, Davis & Christidis 1997
    LUCID Key: Webb & Suter 2010 (genera)
     More ›››  key to genera