Termites, mantids and cockroaches are closely related, and the name Dictyoptera has been erected to name the group. Cockroaches first evolved in the early Carboniferous period, about 359MYA. Mantids evolved from “proto-cockroaches” about 145MYA in the very early cretaceous. So, as Tyrannosaurus rex was romping around biting chunks out of Ceratopsians, early mantids were munching their way through small invertebrates on a micro level. Proto-cockroaches (or Blattoptera) are cockroach like insects that the true cockroaches first evolved from. Looking at a large cockroaches’ leg, you can see the numerous large spines projecting downwards from the leg. It is not hard to see how these could have evolved into raptorial appendages. Termites are just social wood eating cockroaches. They probably evolved about 120MYA in the Cretaceous from a similar group to Cryptocercus, a small wood eating cockroach. Genetic studies have shown that Cryptocercus shares more DNA with termites than any other genus of cockroaches. It is the only cockroach to exhibit true social behaviors like caring for it’s young. I always find it funny when I say “cockroach” to people, and get a repulsed face. Say mantis or termite to them, and they usually hold them with regard and respect in their mind. You now know that they are basically the same thing.
Cockroaches are best known for being pest insects, which some of them are. But only 25-30 species out of the 4,000 around today are pests. They are generally tough animals, able to survive for a long time without food or water. Indeed, that old myth about cockroaches being able to survive for a month without it’s head is actually true!
Blaberus giganteus, the giant cave cockroach. At up to 90mm long, this is one of the longest cockroaches. Males are slim and fly well, but females have such massive bodies that the best they can manage is a sort of controlled fall. Males are often aggressive to each other, and both sexes release a very pungent smell which always reminds me of a nice vaguely fruity chemical. A few nymphs of this species usually retail for a couple of quid each.
The second species is one that I have yet to photograph properly, due to their small size and fast speed! This is Blaberidae sp. “Kenya”. Notice the “dae” on the end of that name. This means that this species is only known to family level, not even genus (like the above species). Males are an appealing orange colour, but females are a dark brown with reduced wings. They are only small at 10-12mm, but I am really looking forward to breeding them.
Now we look at Pycnoscelus sp. " Malaysia”, a small parthinogenic species (where females can produce offspring without a male) related to the sort-of-pest-sort-of-not Pycnoscelus surinamensis which causes a problem with its size and speed by being able to do well in most conditions (as long as there is a lot of moisture), so it jump’s animal tanks easily. They are tiny, which adults rarely reaching 10mm.
Finally, we have a new colour form of Eurycotis opaca, a large species up to 50mm long. It is related to pest species, but is itself not a pest. It has the build of a running species, but it is much larger than most. Adult’s have a blaze of colour on the pronotum which looks to me vaguely like a setting sun.