1. University of Sulaimani
College of Science
Department of Biology
2nd Class Year
Practical Entomology
2010-2011
9 Lab. th
External Morphology
Abdomen and Abdominal
Appendages
Lecturer: Farhad A. Khudhur

2. Objective
• To provide familiarities with basic structure of
insect abdominal region.
• Giving basic knowledge about reproductive and
non-reproductive abdominal appendages.

3. Basic Structure
•The abdomen of an adult insect typically consists of 11
to 12 segments and is less strongly sclerotized than the
head or thorax.
•Each segment of the abdomen is represented by a
sclerotized tergum, sternum, and pleura.
•During the embryonic stage of many insects and the
postembryonic stage of primitive insects, 11 abdominal
segments are present.
•In modern insects there is a tendency toward reduction
in the number of the abdominal segments

4. Basic Structure
•The pregenital segments in male insects are
numbered 1 through 8.
• The pregenital segments in female insects are
numbered 1 through 7.
•Biologically, the abdomen of insects plays an
important role in respiration, reproduction,
digestion, excretion and intermediate
metabolism.

5. Abdominal Appendages
-Respiratory structures (gills, Siphon)
-Cerci
-Caudal Filament
-Genitalia: mating/oviposition structures of adults.
adults

16. References
• Imes, Rick. (2000). Beginner’s guide to Entomology. London.
Chancellor Press, 160 pp.
• Gillot, Cedric. (2005). Entomology. 3rd ed. Springer,
Dordrecht., The Netherlands. 831 pp.
• Resh, Vincent H. & Cardé, Ring T. (2003). Encyclopedia of
Insects. USA. Academic Press, Elsevier Science, 1266 pp.
• Elzinga, Richard J. (1997). Fundamentals of Entomology. 4th
ed. New Jersey, Prentice-Hall, Inc. 475 pp.