Egg squirting roach?

Wh1teshark

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Yesterday when I fed my G. Pulchra a big female B. Dubia she squirted out eggs when she sunk her fang in it's head. They were white and ended up under the munching spider. I didn't dare to take them out because I didn't want to disturb her feast. Today when I looked they were gone.
I assume that my Pulchra ate them.

Has anyone seen this before? Is it some kind of "last resort action" taken by the roach when it feels the end is near? Let's say she laid her eggs where I didn't see them, would they hatch in that enviroemt or do they need alot of moisture to hatch?

Does anyone know how long it usually takes between the eggs are layed untill they hatch? I havn't seen any roach nymps in their rubbermaid yet.

thanks,

/David
 

birdmanson

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I've heard about this phenomenon before. I think It's one of many ways for roaches to secure future offspring. The female roach store the eggs inside her til they hatch, but they can be hatched outside her to. So by squirting out the eggs when facing death she secures that the offspring can continue spreding her genes. The same thing happens when you step on a roach. They r damn good survivours those little critters...:D
 

Code Monkey

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B. dubia eggs are produced as a cylindrical ootheca - it's unlikely they would "squirt out" under any circumstance short of you squishing her with a size 10 boot and rupturing the ovarioles. That said, it's possible that the abdominal muscles responsible for holding the ootheca internally may have fired as a response to an accidental stimulation from the fangs and venom invading the roaches system and expelled the ootheca.

As for their eggs, the ootheca is held internally for about 30 days and then, like hissers, the young hatch internally and the nymphs and the remaining "eggshells" are expelled.
 

Code Monkey

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Originally posted by birdmanson
I've heard about this phenomenon before. I think It's one of many ways for roaches to secure future offspring. The female roach store the eggs inside her til they hatch, but they can be hatched outside her to. So by squirting out the eggs when facing death she secures that the offspring can continue spreding her genes. The same thing happens when you step on a roach. They r damn good survivours those little critters...:D
Your information is wrong.

B. dubia, and (almost) all internally incubating species of roach ootheca will not hatch externally. The ootheca dessicate and die rapidly. *No* roach for any species will hatch from loose eggs from the ovarioles from stepping on them because they're not even fertilized yet. Sperm doesn't enter the egg until the point of laying and then it moves through a small pore in the egg casing. No ootheca means zero chance of hatching.

I include the (almost) above because there may possibly be some species that are very recent on the 'hold'em inside' method of hatching whose ootheca can survive externally, B. dubia is definitely not among them.
 

Wh1teshark

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CM - It was twitching violently when the T got her, so your theory sounds pretty reasonable. One of my B. Dubia in their tank had gotten rid of all her eggs and they were hanging from the behind. Those were a pinkish color and they fell of after a while. Do you think that these were infertile? The eggs that the now eaten roach produced were white in the color.

Thanks for your good reply.

Birdmanson - If I get any nymphs i'll bring you a few to stockholm.

/Dave
 

birdmanson

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wow, you sure know a lot about roaches Code monkey. Thats good, because I've always thought the eggs could hatch outside the mother. Thanks for enlighting me...:) Perhaps I dare to buy some of those critters for spider-food now...


Sounds great sharky...We'll soon meet again, old friend...:D
 

Wh1teshark

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You really should Birdman. Then you won't have those stinking crickets sound-polluting your apartment.

CM - I have a layer with peat moss in my rubbermaid where I keep the Dubias, should I keep it a bit damp or bone dry? They have a waterdish and fresh fruit.

/David
 

Code Monkey

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I keep B. dubia bone dry (and don't even use any substrate). The adults produce enough frass to give the young something to craw around in.

As for knowing about roaches, I'd better. I work for and am a full time graduate student for the urban entomology professor at VA Tech. Roaches are one of our bread and butter bugs.

Now, just to add to the information. There are some species of roach that have external ootheca such as the common German cockroach and the American cockroach. Some of these, such as the Germans, simply carry the ootheca around until it hatches. Others such as the Americans only carry it until they are finished forming it and then they deposit is somewhere. Some of these types of roaches will abandon the ootheca when threatened as a survival mechanism for both parties, mom can run faster and the ootheca may not get munched - this may be where the misunderstanding arose from.
 

birdmanson

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Had a couple of German roaches in my apartment last year. That was not funny. Think they came up from the sink or somewere in the bathroom. Haven't seen any since last winter though...
 

Code Monkey

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Originally posted by birdmanson
Had a couple of German roaches in my apartment last year. That was not funny. Think they came up from the sink or somewere in the bathroom. Haven't seen any since last winter though...
A common misconception is that they can travel through the pipes but this is incorrect (the sink traps stop them). However, they will travel along the outside of pipes and, moreso, need a source of water to live longterm so they are attracted to kitchens and bathrooms. In apartments where infestation is possible it is important to caulk up around where the pipes exit the walls because this is a point of entry for them.

A few Germans is nothing to worry about, but if they become a common pest, use a bait system that has hydromethylon (think I spelled that right) as the active ingredient. Most of the sprays and over the counter baits aren't really that effective but hydromethylon is still effective with no known resistances in the populations.
 

Wh1teshark

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I have never had roaches in my apartment exept for the ones in my Rubbermaid but I did have an infestation of what we in Sweden calls silverfish. It's a small silvery bug that's really hard to get rid of. Anyone know what they are called in English from this lame description?

I have found a new favourite food for my B. dubias. Litche fruit.
Mine allways choose that one before orange, lettuce and dry cat-food. Rather expensive but I have found them to be better lasting than the other.

here's a picture.
http://www.lancetilla-oimt.hn/jardin_botanico/imagenes_jb/image010.html

try it :)

/David
 

Wade

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I got a little confused and thought the picture was supposed to be of the insect and was scratching my head until I re-read the post!

We call them silverfish here as well. Family Lepismatidae.

Wade
 

Wh1teshark

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Kind of off topic but I have found remains of Silverfish in tiny cobwebs behind drawers and other hidden places. I just hope that it's my tiny, freerange, A. geniculata that caught them and then moved to another location since I havn't seen the actual spider.

:)

Wade: I can image it being rather confusing seing that pic and reading about silverfishes. ;)

Regards,

/David
 
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