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Interested in a 2022 BugGuide gathering in New Mexico?

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

National Moth Week 2020 photos of insects and people.

Photos of insects and people from the 2019 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.

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TaxonomyBrowse
Info
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Phylum Arthropoda - Arthropods

Syrphid Fly - Helophilus fasciatus Chalcididae, dorsal - Conura side - female Armored scale insect on pinyon, lateral - female genitalia - Plagodis phlogosaria - male Which spider wasp is this? - Astata Cicindelidia punctulata punctulata - Cicindelidia punctulata - female Male, Ichneumon Wasp? - male Scleropogon coyote
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)