Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Clickable Guide
Moths Butterflies Flies Caterpillars Flies Dragonflies Flies Mantids Cockroaches Bees and Wasps Walkingsticks Earwigs Ants Termites Hoppers and Kin Hoppers and Kin Beetles True Bugs Fleas Grasshoppers and Kin Ticks Spiders Scorpions Centipedes Millipedes

Calendar
Upcoming Events

Spring 2021 gathering in Louisiana, April 28-May 2. Here's how to add your images.

National Moth Week 2020 photos of insects and people.

Photos of insects and people from the 2019 BugGuide Gathering in Louisiana, July 25-27

Discussion, insects and people from the 2018 gathering in Virginia, July 27-29

Photos of insects and people from the 2015 gathering in Wisconsin, July 10-12

Photos of insects and people from the 2014 gathering in Virginia, June 4-7.

Photos of insects and people from the 2013 gathering in Arizona, July 25-28

Photos of insects and people from the 2012 gathering in Alabama


TaxonomyBrowse
Info
ImagesLinksBooksData

Phylum Arthropoda - Arthropods

The Soothsayer Dart - Graphiphora augur Attracted to lights - Patalene olyzonaria - male Margined Blister Beetle - Epicauta funebris Trigonorhinus rotundatus Northern Scurfy Quaker Moth - Homorthodes furfurata Contrachelus sp.? - Conotrachelus elegans Please help us to identify this wasp. - Polistes metricus Saw fly larva ? - Atomacera decepta
Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Explanation of Names
from the Greek arthron (αρθρον)- "joint" + podos (ποδος)- "of foot, leg"; refers to the jointed legs of all members in the phylum
Numbers
Worldwide:(1)(2)
15 classes
>120 orders
~2140 families [doesn't sound right, as Crustacea alone have >1000, Myriapoda close to 200, Arachnida and Hexapoda close to a thousand each, too... =v=]
>1.3 million described species (plus many more undescribed)
Size
ranges from the smallest mite (about 0.10 mm) and the smallest insect (a Hymenopteran, Dicopomorpha echmepterygis at 0.139 mm), up to the Japanese Spider Crab (legspan to 3.8 m), but most arthropods are in the range 2-25 mm
Identification
Three or more pairs of jointed legs (some mites have less, many insect larvae have none)
Body segmented, bilaterally symmetrical
Possessing an exoskeleton, usually tough, composed in part of chitin(2)
See Glossary for terminology.
Range
Cosmopolitan
Habitat
Almost every habitat
Internet References
Introduction to the Arthropoda (Waggoner & Collins)
Tree of Life (Maddison 1995)
Insect Morphology (illustrated glossary)