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Do any insects spend their entire lives underwater?

I received a question from one of my students and it stumped me. Maybe someone out there knows. Do any insects spend their entire life underwater? I am sure there is some somewhere since anything you can imagine it seems an insect is doing.

seal lice, Echinophthiriidae. They do not need to ever leave the water, but they can find and stay in air pockets in the fur of their hosts.

Very Interesting
Very Interesting

I don't know about insects but a spider Argyroneta aquatica

More on aquatic insects
Here's a summary of information I got from an acquaintance, Jerry Freilich, the former Research Coordinator at Olympic National Park and an aquatic insect ecologist, who passed the question on to Boris C. Kondratieff, Professor of Entomology and Director, C. P. Gillette Museum of Arthropod Diversity at Colorado State University.

Jerry's comment was that he thought all insects would emerge from water to disperse and mate, even if that's only 1% of their lifespan.

Dr. Kondratieff wrote:
"Probably the longest lived underwater insect are adult Elmidae, the riffle beetles, supposedly adults can live for 9 years or more under water. Mating is still during a short terrestrial existence (see Elliott, J. M. 2008. The ecology of riffle beetles (Coleoptera: Elmidae) Freshwater Reviews 1: 189-203.). The stonefly genus Pteronarcys aquatic nymphal lifespan and development is 4 years for several species studied. Dytiscidae beetles, predaceous diving beetles mate underwater (see Miller, K. B. and J. Bergsten. 2016. Diving beetles of the world. John Hopkins University press, Baltimore, Maryland)"

Very Nice
Wow! that is very nice. Thank you so much for that info. I earned a lot!

Aquatic Insects
I guess it depends on what you mean by "entire life" and "underwater."

Here are a few resources:

“Insects can’t live in water. Although no insect species lives its whole life-cycle in water without access to air, many insect species pass their nymphal stage in freshwater, breathing with gills.”

In this case, they mean that oxygen is exchanged across the very thin cuticle of gills between water on the outside and air in the tracheae.

In case the Google Books link breaks:

Oxygen diffusion
R.F. Chapman's The Insects Structure and Function (my copy is 1971) has a chapter on respiration in aquatic insects. There's no statement in that chapter that gives an absolute answer to the original question.

A correction to my comment about oxygen diffusion, though:
insects do get some oxygen by diffusion across the cuticle from water to hemolymph. Diffusion of oxygen in hemolymph is slow by comparison to diffusion in air in the tracheoles, however. Some small first instar Dipteran larvae may get all their oxygen with this method, as their tracheoles are filled with fluid.

Thank You
Yes, very interesting and informative. I will pass the information on. However, I think part of the question related to the fact that many larval and nymphal stages were under water while the adult was often terrestrial. Do you know of any that spend all stages of their life underwater?

all stages underwater
No, but maybe someone on bugguide will. I have one more resource I'll try.

To clarify what I wrote above, insects exchange oxygen across cuticle, but always from water to air. Real aquatic animals, like fish and crustaceans exchange oxygen across a membrane from water to bodily fluids.

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