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Home » Guide » Arthropods (Arthropoda)

Phylum Arthropoda - Arthropods

Representative Images

Stagmomantis carolina Phorid Dark Fishing Spider - Dolomedes tenebrosus beetle060319-4 - Capnochroa fuliginosa Unknown grass or wolf spider found in home - Trochosa terricola bee - Coelioxys Pleasing Fungus Beetle - Triplax thoracica Flower Spider - Lateral - Nopalityna sublata - male

Classification

Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)

Explanation of Names

'joint-legged'

Numbers

20 classes, >160 orders, ~4,200 families, and ~1.2 million described species(1)

Size

ranges from the smallest mite (~0.1 mm) and the smallest insect (a Hymenopteran, Dicopomorpha echmepterygis at 0.14 mm), up to the Japanese Spider Crab (legspan to 3.8 m), but most 2‒25 mm

Identification

Three or more pairs of jointed legs (some mites have less, many insect larvae have none)
Body segmented, bilaterally symmetrical
Exoskeleton, usually tough, composed in part of chitin
terminology glossary

Range

Cosmopolitan

Internet References

Higher taxa of Arthropoda (Kluge 2000)

Works Cited

1.Catalogue of Life
Contributed by Troy Bartlett on 31 January, 2004 - 4:45pm
Additional contributions by cotinis, John VanDyk, Beatriz Moisset, Robin McLeod, Chris Wirth, Chuck Entz, ceiseman, v belov, Harsi S. Parker, Blocky, Arturo Santos, Chris Angell
Last updated 6 October, 2025 - 10:12am

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