Worms ~ Some common freshwater types with links to Micscape resources

There are a number of groups of worms that occur in freshwater. Many aren't microscopic but are shown here to give an overview of these groups. Some common organisms that may be confused for a worm are also included.

Note: this table isn't comprehensive, there are several other freshwater groups like ribbonworms and horsehair worms.

Group

 

Key features

Micscape links

Flatworms
(Platyhelminthes)

flattened, 2 or more eye spots, move in gliding fashion
1 - 15+ mm

image of flatworm

Segmented worms
(Annelids)


oligochaetes: 1.5 mm. to >2cm long, hair bundles, (includes earthworm and Tubifex)

leeches: characteristic 'leech-like' motion, suckers each end
>1 cm

image of oligochaete

Roundworms
(Nematodes)

move very frantically, often in 'S' curves,
0.2 - 10 mm

image of nematode

not to be mistaken for worms:

Hydra, has tentacles
extended: 2 cm

Introduction to hydra

larger ciliated protozoa like Spirostomum (has very fast contraction)

Spirostomum

insect stages like mosquito larva, these have a more distinct head than the worms above, also antennae/legs

Go to arthropods overview

 

Protozoa

First Page

Arthropods

Algae

Collecting tips

Insect stages

 



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