Unexpected but somewhat common mistake: Lacewing Eggs vs. Slime Molds

Hey folks,
I was making some IDs today and I wanted to take the time to point out a common mistake I’ve been seeing to help deter some incorrect IDs in the future. Lacewing eggs are placed on long silk stalks that make them somewhat resemble the stalk and sporangium of certain slime molds, like some species of Physarum. It is an easy mistake to make but it results in a kingdom disagreement! Anyway I am thinking of putting together a journal post because there aren’t many resources discussing this specific confusion at the moment so if you have any additional information or pictures that I can include please let me know! So far the key differences that I’ve picked up on are the pretty consistent nature of the lacewing eggs compared to the variability of the slime molds’ sporangia and the length of the lacewing silk stalk being considerably longer than the stalks of most slime molds.

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Slime mold sporangia typically appear in largish groups. I’ve never found lacewing eggs in clusters of more than a few eggs.

Lacewings can be a source of confusion at all life stages – it’s not just the eggs. I imagine this is at least partly due to a lack of familiarity with them, since they are not as conspicuous as many arthropod groups and they are often nocturnal or hide under leaves etc.

I periodically look through observations stuck at Pterygota and as a result have accidentally gotten myself at the top of some leaderboards for dusty lacewings (Coniopterygidae) even though I can’t ID them beyond family. Because of their opaque wings, the adults often get ID’d as whiteflies (Aleyrodidae) rather than lacewings. And the larvae (which are quite colorful) are rather mystifying if you’ve never seen them before; I’ve seen them identified as bug nymphs, aphids, mites, springtails, etc.

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Lol Lacewings are definitely one of the most misidentified taxa that I see.

Thank you for this! I will definitely include in my journal post that is a very good jumping point for identifications

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I have seen more slime molds than lacewing eggs, so I’m not sure how similar Metatrichia vesparia is to any species of lacewing eggs, especially since lacewings typically have white eggs, but feel free to use this picture I took of some last November, if it is an image you think you could use: https://www.inaturalist.org/observations/191208008

Also, I look forward to seeing the journal post!

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Got me.
https://www.inaturalist.org/observations/173133544

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BBC has great footage of a lacewing laying her eggs.

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No expert here, but the lace wing eggs I see here are (as pointed out) singular and also pretty tiny - barely visible.
https://www.inaturalist.org/observations?taxon_id=483236&user_id=teellbee

You might also want to mention that the glandular hairs of some plants can cause confusion. I uploaded this photo today of a sow-thistle, and the Computer Vision “wasn’t confident” but gave a slime mold as the first in the list of suggestions.

Sonchus

Substrate is a good clue - if it’s attached to a living plant surface, or something inanimate like plastic, it’s less likely to be a slime mold.

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That was fantastic! thank you for sharing!!

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https://www.inaturalist.org/observations/232815930

At my place.

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If you all want to see Lacewings plant milkweeds and rudbeckias both seem to get aphids which always draws Lacewings.

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That’s why this stuff confuses me https://www.inaturalist.org/observations/190032720

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Whoa! Amazing! Here in california (Bay Area) I never see more than one at a time

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Any native plant will do. My biggest aphid attractor in New Mexico is Mirabilis. Yesterday, I watched a hoverfly larva “fighting” a lady beetle larva for its spot. https://aphidsonworldsplants.info/c_hosts_aaintro/

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