Arthropods~ Some smaller freshwater types with links to Micscape resources

Arthropods are characterised by jointed limbs and include major groups like the crustacea, insects, spiders and mites. They have many segments, a tough outer skeleton and many modified limbs. There are many microscopic and macroscopic types that occur in freshwater.

There are several other groups with limb-like structures that aren't arthropods. Check rotifers and hydra on the first page.



key features 

Micscape links

Crustacea - Ostracods

bean-like shell <2 mm

Freshwater crustacea

Crustacea - Copepods

long antennae, tiny eyespot: 0.5 - 3 mm

Freshwater crustacea
Cyclops.The one-eyed pond organism

Crustacea - Water fleas 'Cladocera'

antennae, large compound eye
0.3 - several mm

Water-flea anatomy - a fun interactive suite of images
Water fleas - fascinating pond organisms
The giant water flea Leptodora kindtii
10 mm!
Daphnia collecting techniques parts I-IV

Water bears (Tardigrades) 

8 stumpy legs body <1 mm

See gallery links on the right for some of the finest video clips on the Web of these cute critters!

Hunting for 'bears' in the backyard
The incredible water bear
Water bear video gallery I
Water bear video gallery II

Water mites

8 legs, round body 0.5 - 5 mm

Water mites

Mosquito larvae (e.g. fly)

long body, often moves in S-shaped curves 1 - 20 mm

In praise of blackflies
The mosquito Aedes aegypti and Dengue fever

Other Insect stages

wide variety of forms >1 mm

Go to Insect stages overview: e.g. caddisfly larva, dragonfly nymph, water beetles, etc.

Some larger freshwater crustacea -where Micscape has resources

Water louse (isopod) 10 mmFairy shrimp 10 cm and tadpole shrimp (branchiopods) 10 mm

Woodlouse or waterlouse. An interesting pond organismTadpole shrimp and fairy shrimp: Two rare British crustaceans

Freshwater shrimps (not true shrimps but amphipods)

curved, compressed body centimeter
25 mm

No Micscape resources. (Articles welcomed!)



First Page 



Collecting tips 



This page with links hopefully gives a useful overview, but it's neither a formal identification guide nor comprehensive. Water bears have been included here as well as on the first page, because some resources regard them as an arthropod phyla.

Acknowledgements: Many thanks to all the Micscape contributors whose articles this guide links to. For clarity their names are omitted in the links above.

An Introduction to Microscopy

Comments to the compilers Wim van Egmond and Dave Walker are welcomed.

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