This lab provides familiarity with paleopteran insects, specifically the order Ephemeroptera (mayflies). The objectives are to introduce paleopteran insects and study mayflies in detail. The document describes the taxonomy of hexapods, highlighting mayflies' traits including 12-45 molts as larvae with variable tails, two-winged adult stages, short adult lifespan, and wing and body structures as imagos. References are provided for further reading.

1. University of Sulaimania
School of Science
Department of Biology
2nd Class Year
15th Lab.
Pterygotes-Paleopteran Insects:
Order Ephemeroptera
Lecturer: Farhad A. Khudhur

2. Objectives:
•This lab. Provides familiarities with Paleopteran insects
(Mayflies).
• Students will study old winged insect orders,
Ephemeroptera in detail.
Scientific content:
- Paleopteran insects
- Order: Ephemeroptera (Mayflies)

3. Subphyllum Hexapoda.
1. CLASS. Collembola
2. CLASS AND ORDER. Protura
3. CLASS AND ORDER. Diplura
4. CLASS. Insecta
I. SUBCLASS. Apterygota
ORDERS. Microcoryphia and Zygentoma
II. SUBCLASS. Pterygota
A. INFRACLASS. Paleoptera
ORDERS. Ephemeroptera and Odonata
B. INFRACLASS. Neoptera
a. DIVISION. Polyneoptera (orthopteroid orders)
ORDERS. Orthoptera, Grylloblattodea, Dermaptera, Plecoptera,
Embioptera. Dictyoptera, Isoptera, Phasmida, Mantophasmatodea, and
Zoraptera
b. DIVISION. Paraneoptera (hemipteroid orders)
ORDERS. Psocoptera, Phthiraptera, Hemiptera, and Thysanoptera
c. DIVISION. Oligoneoptera (endopterygote orders)
ORDERS. Mecoptera, Lepidoptera, Trichoptera, Diptera.
Siphonaptera, Neuroptera, Megaloptera, Raphidioptera, Coleoptera,
Strepsiptera, and Hymenoptera

4. Order: Ephemeroptera
• Mayflies (order Ephemeroptera) represent
the oldest order of the existing winged
insects.
• They are unique among the insects in
having two winged adult stages, the
subimago and imago.
• As adults they generally live from 1 to 2 hrs
to a few days, and mayflies spend most of
their life in the aquatic environment, either
as eggs or larvae.

5. Larvae
• 12 – 45 molts
• Chewing mouthparts always functional
• Gills absent in instars early instars.
• Variable median caudal filament (i.e., 2-3
“tails”)

6. Imago
• Wings shiny, iridescent, with hind margins
usually bare.
• Short setaceous antennae.
• Two-pair of triangular, membranous wings with
many veins. The fore-wings are larger than hind-
wings.
• The wings are held vertically at rest.
• Body glossy, upwardly concave trunk.
• Forelegs much elongated, esp. males.
• Caudal filaments usually not hairy, typically
longer, brittle, straight.
• Compound eyes prominent, glossy.
• Mandibles stunted, non-functional.

11. References:
•David, B. V. and Ananthakrishnan, T. N. (2004). General and Applied
Entomology. 2nd ed. Tata McGraw-hill Publishing Co. Ltd. New Delhi.
India. 1184 p.
•Elzinga, Richard J. (1997). Fundamentals of Entomology. 4th ed.
New Jersey, Prentice-Hall, Inc. 475 pp.
•Gillot, Cedric. (2005). Entomology. 3rd ed. Springer, Dordrecht. The
Netherlands. 831 pp.
•Grzimek’s Animal Life Encyclopedia, 2nd edition. Volume 3, Insects,
edited by Michael Hutchins, Arthur V. Evans, Rosser W. Garrison,
•Resh, Vincent H. & Cardé, Ring T. (2003). Encyclopedia of Insects.
USA. Academic Press, Elsevier Science, 1266 pp.