Hi friend,
I may not be to the point on your question but here are some interesting facts and details about cockroach that may try and answer your questions regarding cockroaches.
http://scienceray.com/Biology/interesting-facts-about-cockroach/
By putting her on his back and carrying her away
a male cockroach has an anal style while a female does not have it..
She does not lay eggs and she can not have nymphs without a male
The difference between male and female cockroaches is tough to see unless you get up close to the roach. In the female cockroach, the seventh abdominal segment is divided in two, but it is not divided in the male cockroach.
i think that one is big and one is small
The anal region of the cockroach is used to secrete digested materials. This area is very small and hard to see with the human eye.
No. Only female cockroaches lay eggs. There is no male insect of any kind which lays the eggs. A female cockroach will lay anywhere between 10 and 40 eggs in a batch, and a total of around 30 batches of eggs during her lifetime.
Yes! but once impregnated the female is fertilized rest of her life. This basically means that cockroaches do not need to keep mating to get pregnant.
It could be that the female isn't female at all, but a male that is 'Cross Dressing'. It would more than likely depend on the agencyused.
because they are male.
God Bless
Stag can be a large male specimen of most deer species, or a man without escort to a dance. Females are simply, "unescorted". Female deer are does or hinds.