Jump to content

Parcoblatta care questions.


Recommended Posts

I like the look of these, but i am curios about a few things. Do all species need a cool period? Do they all need rotten wood in their diet? And can they breed at room temps? Thanks in advance!

Link to comment
Share on other sites

It highly depends on the region you got them from.

For ex. The virginica population from the northern region seem to require cold period for the high survival rate whereas the ones from souther US don't seem to require the chilling period. So...if your specimens are coming from northern regions, they are likely to require chilling period.

The only exception to this that I can think of is Parcoblatta americana, and maybe P. bolliana though I can't say for sure on bolliana since I've never acquired specimens from northern region before.

None of the species of Parco that I know of require woods to survive (though they'll eat the wood if given a chance). They can sorely be reared on fish flakes and other typical "roach foods".

Link to comment
Share on other sites

It highly depends on the region you got them from.

For ex. The virginica population from the northern region seem to require cold period for the high survival rate whereas the ones from souther US don't seem to require the chilling period. So...if your specimens are coming from northern regions, they are likely to require chilling period.

How do you know that? It might be very likely that there could be many other factors that killed the P. virginica from northern areas that were kept without a cold period. Or have you tested with the P. virginica from northern areas so many times that you are sure that they require a cooling period?
Link to comment
Share on other sites

I guess Asiablatta kyotensis do not need wood to eat, but I have not kept them without wood before so I do not know for certain. They like it kind of dry conditions as nymphs, but I have not kept very young nymphs or oothecae at dry conditions.

Link to comment
Share on other sites

How do you know that? It might be very likely that there could be many other factors that killed the P. virginica from northern areas that were kept without a cold period. Or have you tested with the P. virginica from northern areas so many times that you are sure that they require a cooling period?

I have tried to rear multiple strains of P. virginica and P. pennsylvanica including from individuals collected in Michigan, Tennessee, Wisconsin, and Oklahoma. In these areas it's clear even in non-roach insects (with the exception of invasive species) that a diapause is needed in some form of the insect's life cycle. This is, of course, a genetically defined strategy that allows the insects to go dormant during adverse conditions, which is always at least a 4 month winter in the case of my state. This "hardwiring" is so strong that in these northern genotypes, even when reared in captivity in perfect conditions which have proved successful for culturing the same species only acquired from the south, the colony will crash and in many cases either subadults simply will not mature, will mature with severe body deformities, or will continue to perform stationary molts for months on end before eventually dying.

It is entirely possible, however, to breed out the need for diapause. There is variation in every population which allows it to adapt to new conditions (this is a byproduct of varying conditions year to year, so there are always gene combinations for things that may not be prominent in a population until certain conditions select for them), and it is possible to collect a large number of wild individuals, produce a large number of offspring in captivity (I would say over 100 offspring is crucial), and then let things run their course. In the F1, there will be high mortality over time, but instead of all individuals dying or not reproducing there may be one or two that emerge with normal features or are not deformed enough to reproduce. These produce the F2s, and it can be presumed that since the other F1 and original individuals are not breeding, only the F2s will pass on their genes to the next generation. Over the course of many years (because there was the initial genetic diversity which provided non-diapausing individuals) the most vigorous individuals are able to survive and breed and by the time an F15+ is produced, the strain will have no diapausing requirements because there is no longer the selective pressure of winter on the population.

It's all about the number of individuals used to start the colony and, subsequently, the number of F1s produced. Still, it is extremely difficult the further north you acquire the strain from, as the selective pressure in the environment is extremely intense for favoring diapause there, which may mean the genes for non-diapause are either scarce or nonexistent in the populations. I have all but given up on culturing the native genotype of Parcoblatta virginica in my area as they appear to need a very long, very cold diapause, and the species is not common here which suggests this may be the northern end of their range, and the species cannot/has not adapted an effective way of surviving the winter. Parcoblatta pennsylvanica, on the other hand, graciously tolerates a cooling period of 5 months at around 60 degrees Fahrenheit and is very easy to propagate beyond F1s after satisfying this requirement.

Link to comment
Share on other sites

Happy1982: Thanks for the info regarding the Asiablatta kyotensis, i do not have much rotten wood by me, so i try to avoid inverts that need it.

Zephyr: Thanks for that enlightening info! It is interesting ( and probably frustrating ) how they will refuse to do well in conditions different from their natural habitat.

Link to comment
Share on other sites

I still have doubts on whether they need a diapause.

I have tried to rear multiple strains of P. virginica and P. pennsylvanica including from individuals collected in Michigan, Tennessee, Wisconsin, and Oklahoma.

I have all but given up on culturing the native genotype of Parcoblatta virginica in my area as they appear to need a very long, very cold diapause, and the species is not common here which suggests this may be the northern end of their range, and the species cannot/has not adapted an effective way of surviving the winter.

But because you have done it so many times with Parcoblatta pennsylvanica and P. virginica from several states here in the US, and because I assume you have tried many times with the Parcoblatta virginica in your area, there does seem to be a need for diapause for some reason.

Still, it is extremely difficult the further north you acquire the strain from, as the selective pressure in the environment is extremely intense for favoring diapause there

It is interesting that the farther north you go the worse it gets for the need for diapause.

I was thinking that it was disease and a new diet that might cause your P. virginica that you thought needed diapause to die (diapause maybe could help them adapt, but I have no idea.). I will have to try putting my "Possible caudelli" and P. uhleriana in the refrigerator for a period of time, it might help because I have trouble with those two species disappearing (I think they die) mysteriously.

Also maybe it is built in the genes of the northern types of P. virginica to make chemicals (like anti freeze like stuff) when they reach a certain age, where in the wild it would be winter at that time, and stop making it when they reach the age where in the wild it would be late spring or summer, and those chemicals hinder the roach in fighting bacteria, fungi and other things that are diseases (at cooler temperatures I think these fungi, bacteria etc. do not grow as fast and so would not be attacking the roach so badly when the environment is cold. I could be wrong about this and everything that I wrote I have no idea.). And it is built in the genes of the southern types to make a smaller amount of the chemical stuff and so are not so badly effected when kept without the cold period. These are just wild guesses and I have not read or thought about it much so I could be totally wrong.

Link to comment
Share on other sites

Also maybe it is built in the genes of the northern types of P. virginica to make chemicals (like anti freeze like stuff) when they reach a certain age, where in the wild it would be winter at that time, and stop making it when they reach the age where in the wild it would be late spring or summer, and those chemicals hinder the roach in fighting bacteria, fungi and other things that are diseases (at cooler temperatures I think these fungi, bacteria etc. do not grow as fast and so would not be attacking the roach so badly when the environment is cold. I could be wrong about this and everything that I wrote I have no idea.). And it is built in the genes of the southern types to make a smaller amount of the chemical stuff and so are not so badly effected when kept without the cold period. These are just wild guesses and I have not read or thought about it much so I could be totally wrong.

The mechanism could be as simple as a single chemical production (which is ultimately what all biological responses boil down to really). The diet for my roaches is consistent throughout the year as are the bin conditions, so I doubt that it is either of these. Another species that has proven tough is I. deropeltiformis; cultures collected from TN and even AL tend to fizzle out over time. I have gotten to F3 with those but then the deformed adults simply refused to reproduce afterwards.

Considering there appears to be a spectrum for these perceived diapause requirements I would think there may be multiple genes responsible, with at least one for the "simple" chemical/mechanical mechanism behind it and another for regulating the extent.

Hi, I was just wondering, when do you start to cool them down, and when do you stop?

For my pennsylvanica, I put them in cooling at the beginning of October and take them out in March.

If you have an old cellar use that, put them in the fridge, put them outside in a bin ect ect

I use a crawlspace-like area in my basement that stays fairly dark.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...