In Coleoptera it consists of a tense elastic membrane, which is quite covered by the mesothorax.
These are the mesothorax and the first eight abdominal segments.
Mesepisterna: in Odonata,- the oblique lateral pieces of mesothorax, meeting dorsally in a ridge.
Prothoracic segment a little longer than the mesothorax which, in turn, slightly exceeds the metathorax.
These beetles, when irritated, make a squeaking chirrup by rubbing together the prothorax and mesothorax.
The next segment is the mesothorax, which is immovably fused to the next thoracic segment.
When it is covered by the mesothorax; it is then usually a mere membrane.
On either side we count nine stigmata, set as before on the mesothorax and the first eight abdominal segments.
mesothorax: the second or middle thoracic ring; bears the middle legs and the anterior wings.
In the Neuroptera there is no material or striking difference between the parts of the mesothorax and metathorax.