10 replies to this topic

[Formiga]

I was browsing this ant photography site (and I strongly recommend it!)

 

https://ant-photo.eu.../formica-fusca/

 

When I realized on the photos that some pupae create a cocoon and some others don't.

 

From my observations on my two colonies, my pupae have no cocoon, they are "naked".

Why is that? Why some pupae spin a cocoon and mine don't?

 

I've seen a video somewhere where ants bury the pupae in sand to help them spin their cocoon.

Both my colonies have sand from the place from where I caught their queens.

One colony has sand nearby, the other one has it but outside of the formicarium, but still accessible.

 

Any hints on this behavior? Thanks guys!

[Manitobant]

In formica, the pupae only stay in the cocoon for part of their development. Once they have developed enough in the cocoon, the pupae are unwrapped and continue developing naked until the worker emerges.

[CheetoLord02]

I have found in general that Formica and Polyergus are incredibly inconsistent with spinning their cocoons. A solid 50% or more of the time, the larva will never bother to spin in the first place.

[JamesJohnson]

I have a colony of Camponotus modoc that refuses to spin cocoons. They always pupate and eclose without a problem but just without the cocoons. No idea why they do. Ants just being ants I guess.

[ANTdrew]

Myrmy’s Law: all things being equal, ants will always do the opposite of what you want or expect them to do.

[Formiga]

Myrmy’s Law: all things being equal, ants will always do the opposite of what you want or expect them to do.

Wasn't that supposed to be Cat Logic? So who learned with whom?  

[Formiga]

Thanks for your replies, guys!

 

I had no idea they could or not cocoon themselves.

 

For what I've seen on YouTube, I had the idea they would always create cocoons.

 

I had no idea Formicas could be unwrapped from their cocoons and finish development outside. It's a safe environment and they are already big enough for it.

I had the idea they would start kicking alive inside the cocoon so that would be the time to be unwrapped. That was my notion of eclosion.

So the pupa is outside finishing its development and there's some time the Life Switch goes on and it's time to stretch my legs and move on, I have some eggs to take care of as soon as I can balance myself on my own legs...

 

Interesting!

Edited by Formiga, September 10 2021 - 4:15 PM.

[PurdueEntomology]

In the subfamilies: Dolichoderinae and Myrmicinae, Proceratinae are naked pupae, Formicinae and Ponerinae are cocoon.  Dorylinae are variable, Eciton are cocoon spinners for all castes, in the Neivamyrmex workers are naked but reproductives are cocoon spinners. 

[eea]

I have a colony of Camponotus modoc that refuses to spin cocoons. They always pupate and eclose without a problem but just without the cocoons. No idea why they do. Ants just being ants I guess.

I've only had a naked pupae in camponotus once

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[CheetoLord02]

In the subfamilies: Dolichoderinae and Myrmicinae, Proceratinae are naked pupae, Formicinae and Ponerinae are cocoon.  Dorylinae are variable, Eciton are cocoon spinners for all castes, in the Neivamyrmex workers are naked but reproductives are cocoon spinners. 

Even then, in Formicinae you have certain genera like Nylanderia, Prenolepis, Colobopsis, and many others that do not spin. I believe in Dorylinae also Labidus spin, but Aenictus do not (although the reproductives might. I didn't actually know that Neivamyrmex reproductives spun, which is pretty neat.) I also believe Ectatomminae and Myrmiciinae are spinners, and Pseudomyrmicinae are not.

[PurdueEntomology]

 

In the subfamilies: Dolichoderinae and Myrmicinae, Proceratinae are naked pupae, Formicinae and Ponerinae are cocoon.  Dorylinae are variable, Eciton are cocoon spinners for all castes, in the Neivamyrmex workers are naked but reproductives are cocoon spinners. 

Even then, in Formicinae you have certain genera like Nylanderia, Prenolepis, Colobopsis, and many others that do not spin. I believe in Dorylinae also Labidus spin, but Aenictus do not (although the reproductives might. I didn't actually know that Neivamyrmex reproductives spun, which is pretty neat.) I also believe Ectatomminae and Myrmiciinae are spinners, and Pseudomyrmicinae are not.

 

Yes, always exceptions to the general observations .  And as we are aware species which may spin cocoons often in captive contexts do not.  I have also observed some Formica species in the wild to have naked and cocoon pupae in the same nest.