8 replies to this topic

[bmb1bee]

Polyergus mexicanus "umbratus" - July 29, 2024

At around 5 PM on July 23, 2024 my friend JenC found some Polyergus queens during a nuptial flight. Heat seems to be their main trigger and they can be found wandering on trails in the late afternoon, looking for hosts. Of the 5 queens he obtained, he saved 2 for me, as well as a queen of their main hosts: Formica argentea. After asking around, Reign identified them as a subspecies of Polyergus mexicanus, which could eventually be its own distinct species as it seems to be genetically different enough from Polyergus mexicanus found in the Sierras. I was unfortunately unable to meet with JenC until July 27, and by then 4 of the 5 queens he caught perished as we were both unable to go looking for hosts that week. Luckily, I found a Formica argentea colony on the way back home and obtained around two dozen workers for the last remaining queen. After trying multiple different ways to introduce the queen to them, I was successfully able to get 8 of them together with the queen. She has been fed and should hopefully last long enough for me to obtain more workers, hopefully even brood if I'm able to get any.

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Edited by bmb1bee, September 6 2024 - 1:41 PM.

[bmb1bee]

Basically, for those curious, the interesting thing about Polyergus is that they are "slave raiders". They cannot feed themselves, so they raid other colonies to bring back brood from and raise as their own to feed them.

[GOCAMPONOTUS]

These are very interesting ants. Hope they do well!

[ReignofRage]

The P. "umbratus" identification is very tentative. The original pictures from JenC show the gynes being much more matte than these images. If the gynes are actually this glossy, P. "laeviceps" is the other option. A better identification will come down to if workers are successfully reared. Good luck.

[bmb1bee]

The P. "umbratus" identification is very tentative. The original pictures from JenC show the gynes being much more matte than these images. If the gynes are actually this glossy, P. "laeviceps" is the other option. A better identification will come down to if workers are successfully reared. Good luck.

Thank you. I'll check the area out sometime to collect workers from. Do P. "umbratus" and P. "laeviceps" happen to overlap in population?

[ReignofRage]

Both species overlap through nearly the entirety of the costal region of California, from Southern California through Northern California. Based on previous records, as you cross the Central Valley, it is only P. "umbratus" which then transitions to P. mexicanus. In the Bay Area, they often times are sympatric.

[bmb1bee]

Polyergus mexicanus "umbratus" - August 4, 2024

There was a problem with the workers I previously introduced. They weren’t making any attempts to groom or feed the Polyergus queen even when presented with food. They also occasionally showed signs of aggression at the queen, who I had to separate multiple times due to workers latching onto her legs. After a few days of manually hand feeding her with a thin paintbrush dipped in nectar (something I picked up from Journey to the Ants by Hoelldobler and Wilson) I was finally able to obtain much more suitable hosts. Since JenC had some Formica argentea founding queens from this season, I was able to obtain a couple nanitic callows from him. These were then introduced to the Polyergus queen along with some brood from my own Formica argentea queen, who was a bit slower in development. I deemed it a success, as there were virtually no signs of aggression; trophyllaxis and grooming occurred within minutes of introduction. Though it was a rough start with a modest amount of hosts, I plan to further boost this colony with brood with the next opportunity I get.

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Edited by bmb1bee, August 22 2024 - 12:14 PM.

[bmb1bee]

Polyergus mexicanus "umbratus" - September 6, 2024 

 

Unfortunately, the queen somehow managed to die the same day that I got more host brood. I offered food to the colony just two days prior, so the only reason I can guess for death was that the workers no longer fed her. This journal might remain discontinued for a while, unless I manage to obtain another colony from someone. I could try to collect a colony of them myself, but currently I am very ill-equipped to collect, contain, and sustain them. Perhaps I could do so one day when my multiple Formica colonies increase in size and I have something to contain the Polyergus in. Then again, collecting queens from flights would be far easier and more sustainable.

Edited by bmb1bee, September 6 2024 - 11:50 AM.

[GOCAMPONOTUS]

So sorry she died. Hope you find a queen of these in the future and they do excellent!