Phylum - Arthropoda

Phylum - Arthropoda 

👉 This is the largest phylum of Animala which includes insects:

👉 Over two thirds of ali named species on earth are arthropods.

- Organ-system present
- Bilaterally symmetrical
- Triploblastic
- Segmentation present
-  Coelomate animals

👉 The body of arthropods is covered by chitinous exoskeletori. The body consists of head, thorax (arthros-joint, poda-appendages).

👉 Respiratory organs are gilis, book gilils, book lungs or tracheal system.

👉 Circulatory system is of open type.

👉 Sensory organs like antennae, eyes (compound and simple), statocysts or balancing organs are present.

👉 Excretion takes place through malpighian tubufes abdomen. They have jointed appendages

👉 They are mostly dioecious.

- Fertilisation is usually internal.
- Mostly oviparous.
- Development may be direct or indirect

Examples:

(A) Economically important insects - 

1. Apis (Honey bee)
2. Bombyx (Silkworm)
3. Laccifer (Lac insect)

(B)Vectors - 

1. Anopheles,
2. Culex and
3. Aedes (Mosquitoes)
4. Gregarious pest - Locusta (Locust)

(C)Living fossil - 

1. Limulus (King crab).

Any Other Examples- - 

Butterfly , Scorpion , Prawn