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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

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Previous events


ommatidium, ommatidia

Ommatidium of Machilis
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
No Taxon (Glossary)
No Taxon (O)
No Taxon ommatidium, ommatidia
Explanation of Names
From Greek ommation little eye, that from ommato to furnish with eyes, plus diminutive suffix -idion (1).
ommatidium noun, plural ommatidia - individual element(s) of an insect's compound eye (oculus). Each ommatidium consists of a lens, cone, rhabdom (photoreceptive structure), and pigment cells. The number is variable--from one in worker ants, to circa 2,000 in a dragonfly, and up to 9,000 in some insects. Each ommatidium is approximately 20 μm in diameter and 100 μm in length (1).
Print References
Gordh, entry for ommatidium (1)
Internet References
Works Cited
1.A Dictionary of Entomology
George Gordh, David H. Headrick. 2003. CABI Publishing.