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Kowal's Lasius fuliginosus

lasius fuliginosus lasius fuliginosus kartonówka kartonówki

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#1 Offline Kowal - Posted May 8 2022 - 8:23 AM


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Another journal which is a repost of my journal on a small Polish forum. 

First season
I've caught a queen of Lasius fuliginosus genus on, most likely, 2020.06.11. The next day I dug out some Lasius niger pupae and few workers, separated them and placed queen with pupae:


Few hours later I introduced the workers too. I took too few workers, I should've taken 1 worker per 5-10 pupae.




The queen started laying eggs, her abdomen became swollen a bit:




All the L. niger pupae are already enclosed or rejected. All the L. fuliginosus eggs have hatched, no new eggs appear, colony has reached stagnation.



Colony was placed in the fridge on 2020.09.17 and taken out on 2020.11.21 with short periods in coldest place in my room before and after fridge hibernation.

Second season

Overwintering larvae became hungry in late December/January. 







First pupae became ready to enclose. This is a critical stage of Lasius fuliginosus development - Lasius niger are known to be a poor host when it comes to opening pupae. If they fail to open any, the colony is doomed. They HAVE to open at least one so that it can free other L. fuliginosus workers. 
When a L. fuliginosus pupa is overdue, the worker inside tries to cut out way through the shell. It reminds me of a walrus, as it looks like a blob with two mandibles sticking out. The video shows that happening.


Some of the pupae were laying around half open, with worker fully hardened inside but unable to get out completely. Fortunately few days later a Lasius fuliginosus worker was walking free of its shell.



Soon the colony had lots of Lasius fuliginosus workers. The colony seemingly stopped growing - but in fact the L. fuliginosus population was growing inside, they have just been replacing Lasius niger workers. I haven't seen them killing each other, but somehow the L. niger population quickly collapsed within the colony.



I have caught another L. fuliginosus queen. I prepared a test tube with very small opening - so only workers could pass through it - in attempt of replicating BartTPs method of introducing new queens. The goal is to allow foragers to make contact with new queen without letting her reach the main nest, where nest guardians would execute her. She would be let out only when she would be covered with workers like the the old queen. 



The new queen didn't get much attention, but I've caught one moment when she was being fed.




Still no workers being constantly tending to the new queen. She had enough of it and broke out of the test tube and immidiately had entered the main tube, where she was met with mixed reactions - most of the workers ignored her, some fed her when asked for food and few were chasing her, attacking her legs. When I was leaving to work no worker was attacking her anymore and she seemed to be gaining attention. Unfortunately I found her dead several hours later - I suspect she came too close to the entrance and attracted the guards. 


There was a new nest attached for few weeks. Some foragers were visiting it, but it was generally ignored. On this day I have noticed they moved almost all of the colony to the new nest. Only the queen with a group of workers were still in the tube.





They have segregated the brood by size in the new nest. Also one room became a dedicated pupation station.





The nest is getting crowded, but ants have decided to use two segments as garbage sites. Instead of cleaning them they prefer to occupy empty test tubes in the outworld.





I put the nest into my fridge. All the workers moved into the nest. Later counting had shown that there was over 1000 workers at that time. No Lasius niger workers were present. While cleaning the outworld I've picked two workers to show that L. fuliginosus have workers of slightly varying size - especially the head size can be different.




Third season

In this year I've placed the nest inside a new outworld and attached a new nest made out of cork and partially filled with rotting wood (oak, birch and pine). I wanted them to build their famous fungus-cardboard nest, they never built anything even though they had some wood/cork available before. This didn't work too, it most likely died early.

They have been taken out of the fridge on 2022.01.27. Three days later they have been placed in new outworld and quickly rushed to investigate new areas, especially new nest - but they didn't inhabit it immidiately, sometimes there was just few workers, sometimes hundreds with a bit of brood.





First food of this season.




Fist pupae of this season.








Almost all of overwintering larvae had already pupated and hatched. The queen was busy laying eggs, her abdomen is so physogastric I am surprised she hasn't popped like a pimple yet. Due to barely any larvae present the colony is a bit lazy.


Edited by Kowal, May 8 2022 - 8:38 AM.

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#2 Offline Kowal - Posted May 8 2022 - 8:45 AM


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Somehow the queen seems to be even fatter.




Finally some fresh photos - photos of both of their nests:



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#3 Offline OiledOlives - Posted May 8 2022 - 9:37 AM



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Beautiful colony! This species is in my top 10 world species for sure.

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#4 Offline Kowal - Posted June 12 2022 - 9:59 AM


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Colony has outgrown both nests. Well, technically, there is still lots of room in the cork one, but they didn't dig in it. They have started using tubing as nesting space, then they have built some (fungiless) structures under the acryllic nest, which was an obvious sign that they have no intention of expanding the cork nest. I ordered Wrocław from Anthillshop.pl (20x20x2 cm nesting space minus the watering chambers) and decorated with red clay:



Workers have scouted it immidiately, but it didn't get much attention for few days. On 2022.06.05 I have spotted first group of workers just hanging around in it rather than scouting, two days later they have moved most of the cork nest in here:



Current (2022.06.12) state of the nests:



There's also a lot of workers living directly in the outworld, they have apparently nested in some existing cavities in cork bark, I can also see a mass of workers underneath it. They've used some of the red clay to expand structures under acryllic nest. 

Meanwhile the nuptial flights of Lasius fuliginosus have started. I've managed to catch/buy 11 queens (10 of which were caught within 1 or 2 km from original queens capture point, the other one was still in the same city). I've placed them in test tubes with plastic plugs, in which I cut holes small enough for workers to pass, but not the queen. Said tubes were placed within outworld. They have been met with mixed reactions - some workers were ignoring them, some were feeding them, some were biting them or dragging them around. Two of them have managed to squeeze through their holes and reached one of the nests - where they were quickly executed by ants guarding the entrances. I've tried introducing two of them to the new nest from backside, to trick the guarding ants, but it didn't work too. Others died out in the tubes, maybe from hunger, maybe from being choked to death - I don't know. For now there is just one last queen alive and she's still getting mixed reactions, but the trophallaxis is more frequent and longer, like she's actually getting fed and not only given a taste.


Original queen is still alive.

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#5 Offline Kowal - Posted August 6 2022 - 5:03 AM


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I haven't wrote anything in a while, a lot has happened in the meantime. 
First of all, the last fresh queen has died. I haven't found all the bodies, as some ran away from their tubes, but there was no sight of a second queen anywhere in the nest. But their death wasn't in vain - it seems workers managed to retrieve conidia from inrabuccal pockets of the queens, as few days after presenting first new queens their activity around the big piece of bark in the outworld increased. Soon I have noticed that in one place they've started doing... something. It was a construction made out of clay pellets, pieces of cotton and general woody debris. It wasn't grown through with fungus, but later I found they have been building the carton structures underneath the bark piece!





Unfortunately I had to destroy it all, as the outworld became more and more infested with booklice. It was partially caused by me being not too consistent with cleaning and partially by ants, which had been sticking dead ants in areas I couldn't reach nor see. At some point, when booklice became escaping outside of the outworld, dozens a day, threatening other colonies, my books and furniture I have decided to become more radical. At first I removed most of decorations from the outworld and vacuum cleaned hundreds of dead ants and pieces of feeder insects. Later I have decided to completely wipe this outworld. I have prepared a new one and started disturbing ants living in/under the bark piece so they would move to the proper nest. In the process I could see well their construction. As I've raised the bark I noticed that that queen is living in that part of the setup, so I just left the bark lifted with some tweezers:


I have also dismantled the small, acryllic nest. Before unscrewing the screws I took some photos with underlight - I love how this photo turned out, white acryllic diffused light so nicely:


On 2022.07.07 I have spotted the queen inside the nest, which was the signal I could start scrapping the old outworld:


The new outworld is more simplistic, this time I have decided to not give ants any places they could potentially hide trash from me. Unfortunately clay has not dried yet and they immidiately began digging underneath the stone, which I intended to be their feeding place:



After disconnecting old outworld and connecting the new one I started taking out workers from the old one... one by one. It was a tedious work, in few hours I moved few hundreds or a thousand of them, but last 200ish workers were hiding in pieces of bark too much, so I left them in there. I have taken pieces of fungus structures, cleaned them of any booklice and placed them in the new outworld and then baked the old outworld to kill any booklice left.

Unfortunately the rescued structures, even though they've seen lots of attention at first, were abandoned and I again have no fungus in this colony.



I have continued adding new queens (with no results), just a few of them as their main flights have already ended. 

2022.07.19 Some eggs:



On 2022.08.04 I have cleaned the outworld a bit and found some dead queen bodies. At first I wasn't bothered, as I was adding new queens, but... I have counted one more dead body than I added queens. I began searching for the queen in the nest, but I couldn't spot her. Usually she's either visible or is covered by lots of workers, so any big pile of them is suspicious. I couldn't see her anywhere... no worker balls in sight, no queen. I began panicking and decided to lift the rock. More than a thousand workers have poured out, but again - no queen in sight. I was feeling down and started to accept it's the end, but in late evening of the next day (2022.08.05) I found one ball of workers in the nest, which after being disturbed (by heating the area with a finger) revealed the queen! She's really thin, most likely done with laying eggs for this season, but she's alive!


I still have no idea where the extra body came from. Did I count incorrectly?

Here's current nest overview:


Edited by Kowal, August 6 2022 - 5:14 AM.

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#6 Offline Kowal - Posted November 27 2022 - 11:49 AM


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Sooo... you remember when I changed the outworld as a method of flighting booklice? It happened again. Long story short - plain, simple and boring outworlds are also the least problematic ones. Booklice will devour any plant matter and ant trash they find, and Lasius fuliginosus are pretty good at sticking the latter into the former. Their new new outworld is just plain clay with one rock in the middle, without any fancy decorative cracks in the clay, just... ground. At least there is no plant matter and I can find where the ant trash is being thrown away so I can clean it. The new outworld was connected on 8.09.2022.

7.09.2022 I have taken a timelapse of two larvae spinning their cocoons:


10.09 queen has shared a glimpse of her royal butt:


More and more ants started residing in the outworld rather than in the nest, even though there were empty rooms (and rooms filled with clay & trash ants were definitely not willing to clean). They started making bivouacs in form of balls of workers huddling together. I have placed two plastic test tubes, which were ignored. Then I replaced them with glass one and they inhabited it - but still made those bivouacs, even when more tubes were added.

This meant only one thing - they needed a new nest. I have ordered a large soil nest (roughly 30x20x2 cm internal space), filled it with sand and clay mixture, attached it on 5.10.2022 aaaand... it was inspected, few tunnels were dug through it but making bivouacs was still preferred over doing some actual work and digging new nesting space  :facepalm: 

So, back when I scrapped the outworld with fungus structures in it I recovered bits of it and placed it in the new outworld. One piece saw some attempts of reconstruction, but generally I considered the fungus story being over before scrapping the new outworld and attaching the new new one. On 12.10.2022 I've noticed that one of clay space dividers my L. fuliginosus did in the nest was covered with something. IDK what it is, but it's the most fungusy thing I've seen them do since scrapping of the old outworld.


On 23.10.2022 I have found a single dead male without his head. Maybe he was supposed to be part of spring alate production, but mistakenly he was allowed to pupate too early?

The colony was clearly heading towards diapause. I have placed the colony in a colder place mid November. That temperature change finally triggered them to dig in the soil nest  :facepalm:I let them dig for a while and when I noticed the digging activity to drop I disassembled the setup and placed both nests in my fridge on 27.11.2022.



Bonus: Lasius fuliginosus react to smell of drying mushrooms (Imleria badia) by running around in full alert mode. https://imgur.com/a/FsRLJMI

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#7 Offline Kowal - Posted February 26 2023 - 2:04 PM


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Fourth season

I took the ants out of fridge on 2023.01.25. After short period in 16°C and another short period in room temperature they were placed in their regular spot with heating available. The colony has started being active very quickly - I've spotted the first pupa on 2023.02.10 and first egg on 2023.02.12. At the moment of writing they are in full spring growth.
Workers have done some renovation around the nest. Most noticeable change was a completely new structure built inside the acrylic nest - they haven't done anything on this scale yet. It is still just a clay structure, I doubt it is strenghtened by fungus, I believe it is dead now and workers are just instinctively building stuff.

Queen became very physogastric. Never before I have noticed that it is possible to see the eggs through the thin membrane of her gaster, this year I have noticed it and took a photo, which after slight edit in GIMP looks like this:

It is noticeable even without editing, but I wanted to highlight this fact as I find it extremely interesting. 
I also managed to take a video of queen laying an egg. In fact, I have filmed two following eggs being laid, but the other video is of much worse quality as I didn't set the lighting yet. Time between two eggs being laid was 10-15 minutes - extrapolating this data gives a rather low 3000-4000ish eggs per month rate. I would expect more from such obese queen and from observations of wild colonies. Polygyny of this species is still a topic which needs exploration - it seems obvious that the massive colonies with nets of trails connecting multiple trees these ants can form in nature must be polygynous, but the only paper on this topic I've found suggested that out of 33 colonies just 2 might be polygynous. 

Few photos taken today (2023.02.26) of both nests and the egg pile structure.


Some structures are being built in the new nest already. I hope they will be solid enough to not fall - so far I can't tell if there is any fungus being grown on them. Sugar water intake is high, which is promising. 

Edited by Kowal, February 26 2023 - 2:14 PM.

#8 Offline Kowal - Posted March 8 2023 - 1:43 PM


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2023.03.03 I have noticed first enclosed pupa. It was a male. He was killed soon after, but 20 or so more are running around the nest unbothered by workers at the time of writing the post. I think male production is intentional this time. 

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#9 Offline antsriondel - Posted March 8 2023 - 3:47 PM


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Wow this is the best parasitic lasius journal I have ever read! Great job!  (y)

#10 Offline Kowal - Posted March 22 2023 - 2:06 AM


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Unfortunately the males were not meant to exist. Most of them were killed by workers, some were dragged out of the nest. In total I've counted 17 males taken out of the outworld (dead or alive) and I can't see any more of them inside the nest. Many pupae were trashed this season, there is a chance that workers sensed that these are male pupae and culled them. There were some suspiciously large pupae in the brood piles, but no other alates came out of them - just very large workers, finally some comparable with the wild workers. They are the largest European Lasius and it shows - the new workers are 5 mm long with empty crop, and their long legs make them feel even larger.
Other bad news: the colony needs a fungus transplant. Workers were trying to build something in the new soil nest several times, but some time later whole structure is gone. The clay one I posted a video of is mostly gone as well. The oldest clay pieces they built are significantly darkened, almost cartonlike, but that must be something else changing its colour. Funnily enough workers do not try using strands of cotton they pull out of their feeding tubes for building - but they are capable of bringing them into a nest for pupation stations. 

Here are some photos from recent times.
Egg pile:



General nest photos:





As you can see they mostly live in one giant chamber, they have filled all previously excavated chambers and refuse to do more in this nest. 

I also feel I should post a photo which shows how deep is the nest they keep their brood in and to what extent are the chambers filled to give you a sense of how many pupae are there:


Plus some outworld activity when. The outworld is nothing special, after booklice infestations I refuse to give my ants anything fancy.


Edited by Kowal, June 22 2023 - 4:22 AM.

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#11 Offline Full_Frontal_Yeti - Posted March 22 2023 - 7:29 AM


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OMG that's crazy piles of pupae in there.


Could you possibly post an image of the "total setup?" I like to see how people's setups look as a whole package together.

#12 Offline Kowal - Posted March 22 2023 - 4:06 PM


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OMG that's crazy piles of pupae in there.


Could you possibly post an image of the "total setup?" I like to see how people's setups look as a whole package together.

Well, 99% of it is on photos above as the only parts left are connecting tubes. The setup is in a Kallax shelf and it's hard to take a photo of whole setup as one nest is one module, outworld in another and the other nest is hanging outside of the unit :D You have to use a bit of imagination to see the soil sandwich nest as it is wedged next to two terraria I keep mantises in, I had to remove one of them to take photos above, it's not viewable normally. 



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#13 Offline Full_Frontal_Yeti - Posted March 23 2023 - 11:15 AM


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^ so cool thank you.
While all the details in the other images are great, it was impossible to understand what the setup's special relationships were.

Seeing how you use the side of the shelf for nest mounting and the actual shelf for the outworld is a neat use of the space.


Like the actual image on the puzzle rather than individual pieces.
When you see a whole image, is when you can really get ideas/inspiration for your own.



Thanks again for the time effort on that,

#14 Offline Locness - Posted March 24 2023 - 9:54 PM


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Nice journal, learned a lot about the species  (y)

#15 Offline Katla - Posted March 25 2023 - 2:25 AM


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Hey Welcome Kowal !! nice seeing you sharing bout those precious lasius !


#16 Offline Kowal - Posted June 24 2023 - 9:54 AM


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A photo I forgot to throw in earlier. I like how it looks.




I have decided that the soil nest is not working well. Their structures kept collapsing over and over again, which suggested to me that either they need a fungus transplant via fresh queens or via wild nest piece. To make sure I used both options at the same time to be completely unable to tell you what worked. I bought a new glass sandwich nest (30x30x2 cm) and filled it with some sand+clay mixture and lots of rotten oak wood, in state of being easily broken into dust by hand. Then I sprinkled some salvaged pieces of carton from abandoned wild nest on top of that. I also inserted a piece of carton into the old soil nest.




Ants began working on this nest immediately. They very quickly started building structures connecting the wild carton to side glass and to each other, for some time there was a nice layer of structures where the carton pieces were, but... then they started removing material from underneath of it and lots of that has collapsed. But what you see on the photo below is quite stable, nest looks like this for 2-3 weeks! 

At the same time the piece of carton inserted into soil nest has gathered lots of attention. I've seen it being expanded to connect to side glass, brood was kept on it, everything was looking very promising aaaaand it's gone, like not just a collapse, I have no idea where the original carton piece was. I could only see soil. On the other hand, the small amount of structures visible on the photo has darkened and is also stable for some time - maybe there is some fungus now?

They also stopped building anything in both nests, I guess they like it crammed and don't feel a need for more nesting space now. 

I tried adopting about 20 new L. fuliginosus queens to this colony. Every single one failed.I also tried adopting one queen on callows and pupae as a new colony - even she was rejected by the colony, which in fuliginosus world means she's accepted in the nest, but not being fed. Which is strange considering I saw trophallaxis multiple times. Her gaster never grew and she decided to take a forever nap within a week. Oh well. At least the original queen in my colony is still alive - which is, by collective Polish L. fuliginosus antkeeping experience, already an achievement. She's no longer as plump, it's past the full growth and now they are going to prolong the season by growing at second gear for few months. The egg pile is also very small compared to what it was in peak season. 

Current photos of the nests:






I also have purchased a new outworld for them, as the old one was sometimes uncomfortably crowded. New one is 60x35x10 cm. This photo shows the whole setup now. The sandwich nests are not easy to view, but unfortunately they don't fit in normal position by a centimeter or two. I am thinking about a solution to this problem. I also consider removing the soil nest altogether, at least until it is actually needed. 


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#17 Offline Jonathan5608 - Posted June 24 2023 - 12:36 PM


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Huge colony

#18 Offline Kowal - Posted February 26 2024 - 4:43 AM


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Fifth season

The ants spent two months in a fridge, starting on 2023.11.23 and ending on 2024.01.23. 

The next day I spotted the queen alive! Considering the rumours about the short lifespan of up to four years I was worried she would pass away this winter. She's from 2020, after all.


On the night between 24 and 25 of January the queen was moved between the nests. I managed to get most of the process on camera, the video is sped up up to four times to make the media shorter. 

Later I found the queen back in the acrylic nest. I missed that move. I don't know how many times did she move between the nests.


Short timelapse of a pupation station: 



Current view of the nests, with closeups on the interesting parts:

Acrylic, with some larvae, pupae all the eggs and importantly the queen:




Soil, with mostly larvae and a bit of pupae:




And oak, which is the primary place of storing pupae:




I think it's natural for them to keep pupae in the more woody, warmer part of the nest and other brood underground. Here they have soil nest above the rotten oak one - just to confuse them a little.

They also received a refreshed outworld, since old one needed some repairs anyway I scrapped all the clay, cleaned it and made it from scratch. This time they have three rocks. They serve absolutely no purpose other than annoying me when it comes to cleaning the outworld. I regret not making it plain and simple, these ants are quite trashy. 


Edited by Kowal, February 26 2024 - 4:45 AM.

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#19 Offline GOCAMPONOTUS - Posted February 26 2024 - 10:31 AM


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Keep up the good work!

Currently keeping
1.Camponotus vicinus. 5 workers
2.Camponotus modoc. 5 workers
3. Camponotus hyatti. 1 worker
4.Veromessor pergandei. founding
5 Linepithema humile. 70-100 workers 5 queens
6. Pheidole Californica. 65 workers
I want: Atta,Myrmecia,Myrmica,Myrmecocystus

#20 Offline Idontexist - Posted February 26 2024 - 12:23 PM


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Absolutely insane colony
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Also tagged with one or more of these keywords: lasius, fuliginosus, lasius fuliginosus, kartonówka, kartonówki

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