In flies of the order

Diptera Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advance ...

, the prostigma (also called stigma anteriore or anterior spiracle) is the

anterior Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position pro ...

of the two pairs of spiracles opening on the

pleura The pleurae (: pleura) are the two flattened closed sacs filled with pleural fluid, each ensheathing each lung and lining their surrounding tissues, locally appearing as two opposing layers of serous membrane separating the lungs from the med ...

. The mesothoracic (anterior) pair is located between the pro- and mesothorax and the metathoracic pair (developed mainly in nematocerous Diptera) between the meso- and metathothorax. The following illustration shows the prostigma as number 13 on the right side of the image. The function of the prostigma (as well as the anterior stigma) is to provide an airway into the insect's

thorax The thorax (: thoraces or thoraxes) or chest is a part of the anatomy of mammals and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main di ...

to facilitate

respiration Respiration may refer to: Biology * Cellular respiration, the process in which nutrients are converted into useful energy in a cell ** Anaerobic respiration, cellular respiration without oxygen ** Maintenance respiration, the amount of cellul ...

References

Merz, B. & J.-P. Haenni. 2000. Morphology and terminology of adult Diptera (other than terminalia), pp. 21–51. In ''Contributions to a manual of Palaearctic Diptera'', Vol. 1. (Eds L. Papp & B. Darvas.) (Science Herald, Budapest.) 978 pp. Insect anatomy {{insect-anatomy-stub