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Upcoming Events

Photos of insects and people from the 2022 BugGuide gathering in New Mexico, July 20-24

National Moth Week was July 23-31, 2022! See moth submissions.

Photos of insects and people from the Spring 2021 gathering in Louisiana, April 28-May 2

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

Photos of 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


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TaxonomyBrowse
Info
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Phylum Arthropoda - Arthropods

Ancistrocerus? - Ancistrocerus adiabatus Is this Bombylius major? - Bombylius major Unknown Aphids - Macrosiphum Wasp - Cheiloneurus - female Palpita moth? - Palpita magniferalis Spider with Eggs on Leaf - Agelenopsis Cheumatopsyche unknown - Aaroniella
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
Print References
Giribet, G., and Edgecombe, G. D. 2019. The Phylogeny and Evolutionary History of Arthropods. Current Biology 29(12): R592-R602. https://doi.org/10.1016/j.cub.2019.04.057
Internet References
Introduction to the Arthropoda (Waggoner & Collins)
Tree of Life (Maddison 1995)
Insect Morphology (illustrated glossary)