The orange-spotted roach is sexually dimorphic – males have full wings (but rarely if ever fly), while females have only wing-stubs. A ratio of 1 male per 3-5 females is ideal…excess males should be preferentially used as food for your collection. Maintaining the roaches at this ratio will provide for a great deal of social interaction (please see Part I, Captive Habitat) and increased reproduction.
Males attempt to bluff intruders onto their territories by rising up on their legs and fluttering the wings. If this fails, a shoving match will ensue, with the loser retreating intact (well, except for his pride!).
The life cycle is 18 months to 2 years…but this is not well documented. Please keep notes and pass along anything new you might learn.
Fertilization is internal, via a sperm packet deposited by the male. Females produce the typical roach oothecum, or egg case, but retain it internally for a gestation period of approximately 1 month.
The young, 20-30 in number, are born alive and reach sexual maturity in 3-4 months (this varies with temperature and stocking levels).
The reduced wing size in female orange-spotted roaches (and similar species) is attributed to paedomorphosis, or the retention of juvenile characteristics, rather than to wing growth inhibition.
Flight muscle is, metabolically, one of the most active of animal tissues, and very “expensive” to support. It is theorized that the resources put into maintaining the flight muscles may, in roaches, take away from reproductive potential. In other words, female roaches are, in essence, “trading” flight for the ability to produce additional eggs. Males of some species are though to retain the power of flight so as to be able to cover more ground when searching for mates.
A description of the journal Cockroach Studies, along with photos of long-winged and wingless species, is posted at:
Image referenced from Wikipedia, here.