u/PuchiUna

As I have posted before regarding "Baby Face"—the diving beetle with a retained larval head—I am writing to inform you that it passed away today. (Death was confirmed on September 9th at 12:40 PM JST).

​First, I would like to apologize for being unable to save this insect, and for keeping it alive until today without opting for euthanasia. Despite trying various methods, it was never able to feed. As its keeper, I deeply regret that I was unable to fulfill my duty to provide both a safe environment and adequate nourishment. I am truly sorry.

​After preparing the specimen, I plan to work with university researchers to write a paper on this case. The paper will most likely be in Japanese, but I hope to share it with you once it is completed. Whether an English translation will be produced is still undecided.

Previous post↓

https://www.reddit.com/r/Entomology/s/zQozTuPblw

※Edit: It turned out to be an 8-minute video. It might not play properly because the file is so heavy. (Even I, the creator, keep getting errors and can't watch it...)

Following up on the last post, I'm sharing an update as some of you asked for more information in the comments.

This time, I observed it after putting it into the aquarium and checked if it would react to food. I felt photos wouldn't convey it well, so I'm sharing everything through video.

Here are a few notes on the video content:

To make observation easier, the contents of the aquarium have been kept to an absolute minimum. Also, you might see something floating, but that is just dirt from the driftwood. It is completely harmless to the diving beetle.

In addition, since I couldn't get pesticide-free aquatic plants in time, I put in plastic plants instead. I plan to provide pesticide-free water plants as hiding spots in the future.

The next update is undecided for now. If I do post, it will likely be to share an interesting observation or to announce that this diving beetle has passed away.

Previous post↓

https://www.reddit.com/r/Entomology/s/Dhz2Yp4ETt

This is additional information regarding my previous post.

To check if the head tissue is functioning, I tested whether it has eyesight. When I exposed it to bright light, it reacted, confirming that it can see. This means the tissue in its head is indeed functional.

Also, regarding this diving beetle, there was a similar case in the past. Here is the URL to the paper:

URL:　https://natuurtijdschriften.nl/pub/1015379/EB1952014321011.pdf

After discussing with a Japanese entomologist, we confirmed that this hasn't been reported in Japan yet, so we have decided to publish this as a scientific paper!

As for what's next, we will be observing how long it can survive in this state. While I am very curious about what's inside its head, I won't be dissecting or cutting it open directly. I believe exploring non-destructive methods like CT scanning would be very much worth it.

Next time, I plan to move it to an aquarium.

Previous post↓

https://www.reddit.com/r/Entomology/s/tXm5hDz6TE

Here is some additional information regarding what I posted yesterday.

First, since there were no comparisons with larvae or normal individuals, I have added photos of them.

Next, since some people suggested that 'the adult head might still be inside the larval exuvia (molted skin),' I illuminated it from below with a light.

In the larval head, light passed through. In the adult with the larval head, however, a shadow was visible inside, suggesting something is contained within it. From this, I believe it is entirely possible that an adult head exists inside. However, it is likely not fully or correctly formed.

I also performed a microscopic observation, but it did not reveal any notable information.

Previous post↓

https://www.reddit.com/r/Entomology/s/eNMBcIcgOs

While I was breeding predaceous diving beetles in Japan, this insect appeared.

Edit: Added additional information↓ https://www.reddit.com/r/Entomology/s/tXm5hDz6TE

Inspired by this video　↓

https://youtu.be/16E37tMA5eY?si=pT7U9Q8CBUwIFHu8

Next time, I want to record it much better.

While the Paraponera clavata queen was out hunting, I managed to capture some microscope footage of the larvae. If I get another chance to film them, I'd like to use screen capture to make the video even clearer and easier to watch.

I recently collected a dealate Camponotus obscuripes queen, but she unfortunately passed away on the very first day. Shortly after her death, a large number of maggots started emerging from her body.

​Camponotus obscuripes is a common species found in the mountainous regions of Japan. However, it seems only about 5-10% of the queens are parasitized like this.

​Are there any maggots or parasites that target the Camponotus genus in your area as well?

My Camponotus nicobarensis colony has outgrown its nest.

It’s a bit of a forced move, but they definitely needed a bigger home.