Yellow eggs on locust tree bark (images after hatching added)

[rjlittlefield]

Crossed-eye stereo:




This is cha-cha stereo, one shot for each side, standing on a ladder with hands braced against the tree. Camera was an ancient Canon A710 in Av mode at f/8, manual closest focus with no added lenses, built-in electronic flash diffused through a bit of plastic from an LED tube wrapped around the lens. Aligned in StereoPhoto Maker, sharpened with Topaz AI, heavily cropped from 24mm field width.

The backstory is that I noticed two clusters of these yellow things when I was pruning the locust tree in my front yard yesterday.

Noting the uniform size and lack of supporting stalks, I think these are insect eggs and not any sort of slime mold.

But what sort of eggs, I have no idea. This is a non-native locust tree and I have never seen any sign of feeding on it. I do see a yellow banded locust borer beetle once in a while (less than once per year on average), but not near this particular tree, and clusters of eggs laid in the open would not be a good fit for that.

Does anybody recognize these things?

--Rik

[MarkSturtevant]

Locust borer eggs are laid in cracks in the bark of the host tree: https://wiki.bugwood.org/HPIPM:Locust_Borer but I could not find an ID for these eggs.
You will see plenty of the adult beetles in the late summer if you plant goldenrod. The adults pretty much live on those, it seems. They are just as colorful on the underside as they are up top.

[rjlittlefield]

Thanks for the info and link. That description also notes that locust borer eggs are laid in late summer and hatch in the fall, not consistent with these in spring.

I searched the tree more carefully yesterday and found four smaller clusters that were exposed on flat bark so I could collect them with a shallow biopsy. Those have now been relocated to indoors, in front of an MP-E 65 and R7 shooting gigabytes of time lapse. I'm guessing that if I can look at the hatchlings, I can probably figure out at least what order they are. No idea how long they will take to hatch, though.

--Rik

[Marcepstein]

Nice images !!

[rjlittlefield]

Some of the egg clusters that I moved indoors have hatched.

Here's a view by cell phone through a stereo scope:



To me these look like lady beetle larvae, which would make sense given the location, time of year, and the fact that I also saw an adult while searching for more eggs.

Ironically, after I saw the hatchlings, it finally occurred to me to ask Google image search about the eggs. Google immediately suggest lady beetle eggs, plus a couple of slime molds of similar appearance. That's an amazing tool.

Image search is not foolproof though. I asked it about the above picture of the larvae, and it gave me almost entirely unhelpful suggestions. There was one hit for an image at dreamstime labeled "Larvas of ladybugs freshly emerged from their chrysalis". (The author's name suggests not a native english speaker, which would explain the odd terminology.)

The time lapse capture continues. Clearly that batch of eggs is running behind these, but I have no idea by how much.

--Rik

[rjlittlefield]

See viewtopic.php?f=27&t=47246 for a time lapse video that shows hatching for one of the groups that I brought indoors.

After that, it turned out that the eggs I had photographed and left on the tree were the last to emerge.

For those, I checked periodically and was lucky enough to catch them in early hatch.

Following is a series of images showing the early hours of hatching.

These are stacks, shot on the tree under conditions that were a bit awkward. I had to place a stepladder and stand on the third step, reaching out with a Canon MP-E 65 lens on R7 camera, with a 580EX II flash and diffuser on bracket, and somehow maintain frame and focus whilst the wind gusted around me. After several horribly failed attempts, I finally got smart enough to go whittle a stick that was a suitable length to jam between my body and the tree. That added some stability and also provided a platform along which I could slide the camera while shooting continuously in burst mode. The result was something like 2.5 frames per second, but even so the subjects were moving around so much that I had to retouch every larva from the one or two frames where it looked the best. Probably that left a spare leg or two somewhere, but the mess of body parts was so confusing I couldn't figure it all out!

April 25, 3:28 pm


April 25, 5:31 pm


April 25, 6:37 pm


April 26, 11:26 am


April 26, 3:54 pm


In this larger clutch of 23 eggs, I think I count one that developed a little too slowly and got eaten as an unhatched larva, and another three that failed to develop and were eaten as yellow eggs.

Manual f/8, 1/250 second, ISO 200, auto flash exposure on only the first frame of each burst. Stack lengths vary randomly from 18 to 35 frames due to uncontrolled shooting conditions.

--Rik

[mkbn]

Def fascinating! I get a lil creeped out by those since I was photographing aphids last year and these, seemingly preying upon the aphids as adults, and I swear one of the bigger larvae bit at my foot as it crawled around my sandal. I think mine were Asian lasybeetle larvae, though, with the coloration (I also used image search, which is so nice to at least get a lead to start with these days).