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 Major Groups | Crustacea (crustaceans) | Malacostraca (malacostracans) | Isopoda (water slaters) | Janiridae
 

Janiridae
Heterias

Major Group: Crustacea
Minor Group: Malacostraca
Order: Isopoda
Family:
Janiridae
Genus: Heterias
This family has only one freshwater genus in Australia, Heterias Richardson.

Descriptive Features:

  • body rectangular, depressed
  • head and pereonites free, with the lateral parts lamellarly expanded in most genera, pereonites subequal in length
  • pleon usually consists of 2 segments, when present, 1st is narrow and inconspicuous, 2nd large and shield-shaped
  • eyes often present, situated on upper surface
  • antenna 1 almost always longer than antenna 2, with 6 articles in peduncle and with generally well-developed antennal scale
  • mandible with palp, normally with well-developed molar process
  • maxillipedal palp usually with article 3 in particular, expanded, as wide as or wider than endite
  • pereopod 1 usually more or less prehensile, remaining pereopods ambulatory, of moderate and almost equal length
  • dactylus almost always with 2 or 3 claws
  • uropods on lateral or terminal margin, with peduncle, biramous or occasionally uniramous
  • Total length: up to 6 mm
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    Heterias pusilla

    Taxonomic Checklist: Species
    Heterias nichollosi Chappuis
    Heterias petrensis Roberts
    Heterias pusilla Sayce

    Distribution: SA, Tas, Vic

    Sensitivity Rating: SIGNAL grade 3

    AUSRIVAS Taxacode: OR189999

    Functional Feeding Group: shredders

     

    Broken River, Benalla Vic

    Ecology: Instream habitat: Heterias occurs in lotic and lentic waters including, caves, streams, pools and lakes.
    Feeding ecology: Heterias water slaters are detritivores.
    Habit: Heterias is free living.
    Life history:

     

    Information Sources: Hawking & Smith 1997, Poore 2002, Wilson & Wagele 1994
    Key to Species: none