This comprehensive lecture slide covers the Phylum Arthropoda, the largest and most diverse group in the animal kingdom. It is ideal for undergraduate students of zoology, biology, and entomology, as well as educators and competitive exam aspirants. Topics Covered: General characteristics of Arthropoda Subphyla and major classes of Arthropoda Diagnostic features of each class: Insecta, Arachnida, Crustacea, Chilopoda, Diplopoda, etc. Overview of important orders within Class Insecta (e.g., Coleoptera, Diptera, Lepidoptera, Hymenoptera, Orthoptera, Hemiptera, etc.) Classification flowcharts and diagrams for better understanding

1. ENTOMLOGY
By
Miraj Khan

2. Characteristics of Phylum Arthropoda
1.The body is triploblastic, segmented, and bilaterally symmetrical.
2.They exhibit organ system level of organization.
3.The body is divided into head, thorax, and abdomen.
4.Their body has jointed appendages which help in locomotion.
5.The coelomic cavity is filled with blood.
6.They have an open circulatory system.
7.The head bears a pair of compound eyes.
Phylum ARTHROPODA

3. 8. The exoskeleton is made of chitin.
9. The terrestrial Arthropods excrete through Malpighian tubules while the aquatic ones excrete
through green glands or coaxal glands.
10. They are unisexual and fertilization is either external or internal.
11. They have a well-developed digestive system.
12. They respire through the general body surface or trachea.
13. They contain sensory organs like hairs, antennae, simple and compound eyes, auditory organs,
and statocysts.

5. 1. CRUSTACEA
▪ They are aquatic, terrestrial, or parasitic.
▪ The head is fused with the thorax region known as the cephalothorax.
▪ Respiration occurs through gills or general body surface.
▪ The body is covered by a single large carapace.
▪ They possess two pairs of antennae and five pairs of appendages.
▪ They excrete through green glands or antennal glands.
▪ They have a pair of compound eyes and gonopores.
▪ Development is indirect. Larval stage is present.
Eg., Daphnia, Palaemon

6. Classification of Crustacea
6 CLASSES

7. 2. MYRIAPODA
▪ These are mostly terrestrial.
▪ The body is elongated with numerous segments.
▪ The head is provided with antennae, two pairs of jaws, and a pair of simple eyes.
▪ They contain numerous legs.
▪ The upper lip of the mouth contains epistome and labrum, and the lower lip contains a
pair of maxillae.
▪ A pair of mandibles is present inside the mouth.
▪ They respire by trachea and excretion occurs by Malpighian tubules.
E.g. Julus, Scolopendra

9. 3. CHELICERATA
▪ They are mostly found on land.
▪ The body is differentiated into cephalothorax and abdomen.
▪ Antennae are absent.
▪ The abdomen is divided into 13 segments.
▪ It has four pairs of interior appendages.
▪ They respire through trachea or gills.
▪ The Malpighian tubules help in excretion.
E.g. Aramea, Limulus

12. 4. ONYCHOPHORA
▪ These are small-sized, terrestrial arthropods.
▪ The body is divided into segments.
▪ Excretion occurs through nephridia.
▪ They respire through the trachea.
E.g. Paripatus

13. 5. TRILOBITOMORPHA
▪ These are primitive arthropods and are extinct.
▪ They were found in abundance during the Paleozoic era.
▪ The body was divided into three lobes- one median and two lateral lobes.
▪ Head bore a pair of compound eyes and a pair of antennae.
▪ There was no structural differentiation of the body parts.
▪ The body was divided into head, thorax and pygidium.
▪ Appendages are biramous.
The subphylum had only one class- Trilobita

14. 6. HEXAPODA
▪ They are mostly terrestrial.
▪ The body is differentiated into head, thorax, and abdomen.
▪ Head bears a pre-segmental acron.
▪ The thorax is divided into three segments. The abdomen has 7-11 segments.
▪ They have three pair of appendages.
▪ It has a pair of compound eyes
▪ They respire through gills and trachea.
▪ Malpighian tubules are the excretory organ.
▪ Development is indirect, and the larval stage is present.
E.g. Tabernus, Mosquitoes, Ants.

16. 1. Sub Class: Apterygote Insecta
(former Thysanura sensu lato)- Primitive
wingless insects
I. Order Archaeognatha (Microcoryphia;
archaeognathans or bristletails)
II. Order Zygentoma (silverfish)

17. 2 Subclass Pterygota
Divided into two super orders/Divisions;
o Exopterygota
o Endopterygota
▪ Exopterygota ("external winged forms") develop wings on the outside of their bodies
without going through a true pupal stage,
▪ Endopterygota (meaning literally "internal winged forms") develop wings inside the body
and undergo an elaborate metamorphosis involving a pupal stage.

18. I. Division Exopterygota
i. Order Phthiraptera: Biting and Sucking lice
ii. Order Psocoptera : Booklice and Bark lice
iii. Order Blattodea : Cockroaches
iv. Order Odonata : Dragonflies and Damselflies
v. Order Dermaptera : Earwig
vi. Order Orthoptera : Grasshoppers and Crickets
vii. Order Mantodea : Praying Mantids
viii. Order Ephemeroptera: Mayflies

19. ix. Order Phasmatodea: Stick insects and Leaf insects
x. Order Isoptera (Now part of Blattodea: Termites
xi. Order: Plecoptera: Stoneflies
xii. Order Thysanoptera: Thrips
xiii. Order Hemiptera: True Bugs
xiv. Order Embioptera: Web-spinners
xv. Order Zoraptera: Zorapterans

20. I. Division Endopterygota
i. Order Megaloptera: Alderflies, Dobsonflies & Fishflies
ii. Order Hymenoptera: Bees, Wasps and Ants
iii. Order Coleoptera: Beetles
iv. Order Lepidoptera: Butterflies and Moths
v. Order Trichoptera: Caddisflies
vi. Order Siphonaptera: Fleas
vii. Order Diptera: Flies
viii. Order Neuroptera: Lacewings, Antlions & Mantidflies
ix. Order Mecoptera: Scorpionflies
x. Order Raphidioptera: Snakeflies
xi. Order Strepsiptera: Strepsipterans

21. Your slides
Prepared
By
Miraj Khan