B. giganteus / G. portentosa questions! :-D

[Kaddock]

Hello!

I haven't been on in a while...

But, I now have two questions that I was hoping someone knows the answer to:

1: How do I sex Blaberus giganteus?

2: I was under the impression that Gromphadorhina portentosa only eject their eggs to dry the case and then hold them until they hatch... True? I recently seperated about a third of my culture in hopes of seeing some nymphs, as they've reached their "cap" for this cage size it seems. I just gave them a water refill, and noticed two egg cases laying on top of the silk leaves in the enclosure. Are these eggs done for? I was hoping they would produce nymphs after the move, not abort them! :mellow:

 

[bigtoach]

I don't think u will get any nymphs from the aborted ooths. I don't know of anyone that has had much luck, usually they turn yellow and dry out quickly.

Also I was under the assumption that all roaches were the sexed the same way, by the last abdominal segment. Large/wide being female and small/pointed being male.

 

[Kaddock]

I don't think u will get any nymphs from the aborted ooths. I don't know of anyone that has had much luck, usually they turn yellow and dry out quickly.

Well... I got a healthy crop babies from the hisser ooths. Sweet.

Also I was under the assumption that all roaches were the sexed the same way, by the last abdominal segment. Large/wide being female and small/pointed being male.

I'd never really looked into sexing my roaches, so thanks for the information.

I do not think that sexing is limited to this method, however. For example, it's much easier to tell my G. portentosa apart by their more obvious features: the males have horns, hairy antennae, and a different look to them. I was just wondering if there were any features that were more obvious for the B. giganteus.

Surely someone here raises them?! I'll go ask on Mantid forum.

 

[Ralph]

Nothing wrong with the last-segment method, right? Adult male Blaberus usually have thinner, more tapered abdomens overall, and their wings often reach farther past the abdomen than females'.

 

[likebugs]

The last segment technique is what I do. I find that the differences in appearance of genders for some roach species can be subtle.

I find that to be sure on certain species' genders is to look at the last segments. My Eurycotis floridana males and females look very similar to eacher, at a glance. I still have to look at their rears from time to time, the last tergum,(dorsal segment)is shaped a little differently, but is easy to view.

My Blaberus species' males look like a little notch has been "bitten" off of the tips of their last ventral segments. I guess that is another way, but I haven't seen B. giganteus that closely.