I have started work in the lab dissecting and extracting the labial, hypopharyngeal and and mandibular glands from the head of Tetragonula carbonaria (an Australian native stingless bee). I’ve been taking pictures at every stage of this process, in order to document the technique for others who may which to attempt this. The first two pictures provide some context for the dissection. Note how little hair this bee has in comparison to the honey bee and the ocelli on the top of the head: these are simple, light-sensitive eyes. I’m using the same set-up and equipment from when I was dissecting honey bees, although I used a tiny scalpel to make the incisions for this dissection. I would like to acknowledge that the techniques I used were based on writings of Dr. Stefan Jarau who has published some amazingly detailed papers on dissecting stingless bees (although I have done some things differently to make things easier for me). Dr. Sara Leonhardt and Dr. Tim Heard have been providing me with help and advice and I’d also like to sincerely thank Linda Pappalardo for her help in the lab.
T. carbonaria worker under the microscope
T. carbonaria head; note the 3 ocelli on top
The first step in the dissection was to mount the heads of the bees (which had been killed in the freezer) so they would be help firmly in place. I used a variation of the technique for dissecting honey bees by heating up a metal rod, creating a hole in the beeswax with it and then inserting the body of the bee up to the base of the head. I found this satisfactory for holding the head of the bee in place and it enabled a lot of bees to be set in a relatively short space of time.
Mounting T. carbonaria in wax
As I kept practicing, I noticed it was easier to heat up a channel of wax (about 3cm long, 1cm deep) using the length of the metal rod rather than the tip. Then, after cutting off the wings of the bee, you could place it in this wax holding it by the antennae until the wax set around it. The picture below is the result of this technique and seems to be the easiest method so far.
T. carbonaria mounted head
After the antennae were removed with tweezers, the head was covered in an ethanol solution (Jarau recommended a saline solution) and six shallow cuts through the cuticle were made in the areas indicated with the red lines in the picture below. The cuticle was then removed with tweezers, exposing the brain and the glands.
Six lines showing where to cut when opening up the head
My first success has been to isolate the ocelli in the head, which you can see below. As the dissection progresses further I’ll update this article with more news and pictures.
T. carbonaria ocelli removed from the head
T. carbonaria head with the cuticle removed
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