17 replies to this topic

[AntHUB]

During june of 2018 I was just beginning to seriously get into ant keeping. I collected around 100-120 tetramorium queens. Wanting to preserve space in test tubes I put them together as polygynes, fully expecting pleometrosis. To my suprise a few queens actually were successful with polygyny. Unfortunatley I went on two long, back-to-back trips, that resulted in the loss of over 50 of my colonies, including these. one of the queens actually raised the yellow workers on her own (Elbert CO.), they were the same species so I put them together in an alchohol jar.

 

I think the yellow workers are not just cowls, because the polygyne had two generations of yellow workers that never changed color.

 

I believe they are tetramorium because:

workers have square heads more similar to Tetramorium than pheidole,

workers have a generally more porous exoskeleton than what I have observed in pheidole,

Queens have a petiole that matches tetramorium not necessarily matching pheidole

profile of queens similar to many european tetramorium species.

 

All 4 queens collected

 

close up showing some more detail

 

photo showing more accurate colors

[Aaron567]

Definitely caespitum-complex Tetramorium. If it isn't just a case of color variation with Tetramorium immigrans (which has a high likelihood), then there is a slight possibility that it could be a new European or Asian exotic species, although an inland state like Colorado is not typically where a new exotic would show up.

[AntHUB]

Most T. immigrans here does not have this color type, although I have a few pictures of red Tetramorium workers as well. But none are yellow.

except these

[gcsnelling]

Lets get some specimens mounted and some decent pictures and go from there.

[AntHUB]

ok, will do

[AnthonyP163]

I have had this happen to me as well. It is interesting to see the color variations are in many different places.

[Manitobant]

Maybe tetramorium tsushimae? They've been found in the US and I have a colony found in a greenhouse in canada.

Edited by Manitobant, February 18 2020 - 3:59 PM.

[AnthonyP163]

Maybe tetramorium tsushimae? They've been found in the US and I have a colony found in a greenhouse in canada.

Tetramorium tsushimae is not yellow and does not currently have any records near these findings. 

[AntHUB]

 

Maybe tetramorium tsushimae? They've been found in the US and I have a colony found in a greenhouse in canada.

Tetramorium tsushimae is not yellow and does not currently have any records near these findings. 

 

The curation of my state is really bad, it hasn't really been updated since 1963. I am redoing it with the assistance of my local museum. So I don't really take antweb at face value.

[AntHUB]

I don't have access to a microscope image stacking program, that being said, I point mounted these and just used my camera, does that help at all?

queen

worker

[AnthonyP163]

I don't have access to a microscope image stacking program, that being said, I point mounted these and just used my camera, does that help at all?

IMG_3505.jpg

IMG_3508-2.jpg

IMG_3510-2.jpg

queen

IMG_3512.jpg

IMG_3520.jpg

worker

Interestingly the only distinguishable feature I've heard between T. tsushimae and T. immigrans aside from their coloration is that T. tsushimae has more hair on the thorax. I question, however, the reliability of that generalization. 

 

Of course it is possible for T. tsushimae to be in your state. However, given that current records aren't anywhere near it, and that the workers aren't the same color as known tsushimae specimens, I would say it's more likely that it's an odd variant or occurrence in T. immigrans.

[Martialis]

A closer, dorsal view of the worker would be very helpful

[AntHUB]

I need to get another extension tube then, that's my highest magnification

[RushmoreAnts]

 

I don't have access to a microscope image stacking program, that being said, I point mounted these and just used my camera, does that help at all?

IMG_3505.jpg

IMG_3508-2.jpg

IMG_3510-2.jpg

queen

IMG_3512.jpg

IMG_3520.jpg

worker

Interestingly the only distinguishable feature I've heard between T. tsushimae and T. immigrans aside from their coloration is that T. tsushimae has more hair on the thorax. I question, however, the reliability of that generalization. 

 

Of course it is possible for T. tsushimae to be in your state. However, given that current records aren't anywhere near it, and that the workers aren't the same color as known tsushimae specimens, I would say it's more likely that it's an odd variant or occurrence in T. immigrans.

 

I believe many of the colonies around here are tsushimae, as there are two sizes of Tetramorium alates, and some workers have lighter thoraxes like tsushimae. However, it is more likely for them to be here than Colorado, as we're closer to Missouri and Illinois where they're commonly found.

[gcsnelling]

Why not try using this instead of more extension tubes.

 

https://www.amazon.c...1?ie=UTF8&psc=1

[PacificNorthWestern]

this probably isn't it, but i know when workers are newly enclosed, they tend to be more light in color. I have some prime examples in a new colony of mine. I don't think this is a case, just something to think about 

[AntHUB]

I thought that was it until the workers died of natural causes after living for 2-3 months, they were yellow. I emailed Brian fisher, he said that they might be pheidole bicarinata, which fits the description of the species in my opinion.

[Robert]

Hey, I usually just lurk, but I'd like to point out that these guys are likely not P. bicarinata due to the surface sculpture of the gynes' heads. Although they appear very similar initially, the vertical (costate?) lines that run posterio-anteriorly in both T. immigrans and P. bicarinata stop at the posterio-lateral temples of P. bicarinata, while in the case of T. immigrans they continue until out of face view. P. bicarinata gynes also seem to have slight depression on their forehead right between the ocelli, which is also something T. immigrans gynes (and the ones in the pictures) seem to lack.