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Dictyoptera (cockroaches and mantids)
The Dictyoptera are an order in the phylum Uniramia or Hexapoda (depends which book you read), for more pages on this phylum click the menu below left.
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Mantids Are also called praying mantis can be easily distinguished from the cockroaches by their strongly-spined raptorial front legs, and their long, narrow prothorax which forms a moveable neck. All mantids are carnivorous and use their front legs to catch their food. They will eat whatever they can hold on to, and even the very hardest parts of some beetles and wasps pose no problem to their very strong jaws which just keep munching through hard and soft parts. Male mantids are usually smaller than the female, and may end up as a post-coital meal for the female, but this occurs more often in captivity than in the wild. The eggs are laid in oothecae (egg cases). The egg case and eggs are pumped out of the abdomen as a frothy substance. This hardens on contact with the air to a tough material. On the left you can see a female next to the egg case she has just attached to some twigs. During her lifetime a healthy, well-fed female can produce a dozen or more oothecae. When the young hatch they resemble small worms, but soon moult into small versions of the adult form. When kept in captivity mantids should be separated as soon as they hatch or else each cage will soon contain just one well-fed mantid! In captivity they can be fed on flies or crickets or anything that moves. I have even had one attempt to dine off my finger in preference to the small, juicy fly I was tempting it with. Cockroaches Cockroaches have been in existence for over 350 million years (since the Devonian).There are over 4000 species world wide, 130 species in Europe. 3 species are native to the British Isles, other cockroaches were introduced to the UK from warmer countries, probably arriving in cargo carried in ships. They are omnivorous scavengers and will eat almost anything (sometimes even cannibalistic), and active mainly at night. They are considered pests of stored produce because, although they eat only a little, they contaminate large quantities which take on a characteristic smell and have to be thrown away. Also they can be carriers of diseases spread by viruses and bacteria. They are often mistaken for beetles, and the common cockroach (Blatta orientalis below left and right), which was introduced to the UK in the 16th century, is also known as the |
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above a female mantid next to a newly laid ootheca |
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On the left is a female carrying an egg case. As with the Mantids above the eggs are contained in an egg case or purse (ootheca) see the drawing above, and are carried around by the female attached to the tip of her abdomen for a few days before she deposits them; usually near a source of food. The ootheca contains from 16 to 40 eggs depending on the species. Above right is the male with more developed wings. Adult males in the UK fly, but the wings of the females of some species do not develop enough to enable her to fly. On the right is a diagram showing the arrangement of the internal organs of a female cockroach.
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| In the German Cockroach, Blatella germanica, both sexes look alike, with the female being slightly larger. Dnd both have wings reaching the end of the abdomen, also both sexes can fly. The eggs case holds 20 - 40 eggs, and a female can lay up to 7 cases in her lifetime, and need mate only once to do so. It is found world wide, but only indoors in the colder month in the UK. | ||
![[]](http://m3.moostik.net/img/?pseudo=bumblebeepages&cpt=Dictyoptera&option=invisible)