Major Group: Gastropoda Order: Hygrophila Family: Planorbidae |
Descriptive Features: true molluscan gill lost, replaced by various types of secondary gills in some groups
position of eyes relative to tentacles variable, usually at inner bases or at middle of bases
hermaphroditic (simultaneous or protandric)
operculum absent
mantle cavity modified as pulmonary cavity
head and snout spread laterally
radula with many tooth rows (most teeth rather similar)
operculum absent
eyes on inner side of tentacle bases
shell coiled, sinistral, flat to ovate or elongate, spire sunken, flat or short to long
mantle edge simple, with pseudobranch
Size: |
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Glyptophysa sp. |
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Gyraulus sp. |
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Taxonomic Checklist: Genera Amerianna 4? species Ancylastrum 2 species Bayardella 2 species Ferrissia 2 species Stimulator consetti Iredale Glyptophysa 11 species Gyraulus 10 species Helicorbis 2 species Isidorella 5? species Kessneria papillosa Walker & Ponder Leichhardtia sisurnius Walker Planorbarius corneus Linnaeus Note: plus 1 undescribed genus and several undescribed species |
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Distribution: all states
Sensitivity Rating: SIGNAL grade 2
Functional Feeding Group: scrapers |
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Dobson Lake outflow, Mt Field NP Tas |
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Ecology: Instream habitat: Planorbidae species occur in slow-moving and still waters where they are found amongst macrophytes and algae. Feeding ecology: Planorbid snails feed macrophytes and algae. Habit: Isidorella newcombi is able to aestivate in the mud when conditions become unfavourable. Life history: Planorbidae species are hermaphrodites capable of self-fertilisation. They reproduce at least once per year. |
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Information Sources: Ponder 2013, Smith 1992, 1996, 2002c, Walker & Ponder 2001, Gooderham & Tsyrlin 2002, Stevens et al. 1996, Sloane & Norris 2002 Key to Genera: Smith 1996 Key to Species: Ponder et al. 2000 (NSW), Smith & Kershaw 1981 (Tas)
Planorbidae species fall into three groups by shell type; freshwater limpets (patelliform), flat spirals (planate taxa) and elevated spirals (non-planate taxa) |
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freshwater limpets |
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flat spirals |
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elevated spirals |
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