प्रारम्भिक कीट विज्ञान/२

नेपाली विकिपुस्तकबाट, स्वतन्त्र पुस्तकालय
यसमा जानुहोस्: अन्वेषण, खोज्नुहोस्

Insects are invertebrates grouped in the phylum Arthropoda (Subphylum : Uniramia) Characters of the Phylum Arthropoda: (Arthro-joint, poda-foot)

  1. Segmented body
  2. Segments grouped into 2 or 3 regions known as Tagmosis
  3. Renewable chitinous exoskeleton
  4. Grow by moulting
  5. Bilateral symmetry
  6. Body cavity filled with blood-Haemocoel
  7. Tubular alimentary canal with mouth and anus
  8. Dorsal heart with ostia
  9. Dorsal brain with ventral nerve cord
  10. Striated muscles
  11. No cilia
  12. Paired segmented appendages

Classification: 7 classes. Phylum : Arthropoda Subphylum: Uniramia Classes :

  1. Onychophora (claw bearing)e.g. Peripatus
  2. Crustacea (Crusta - shell)e.g. Prawn, crab, wood louse
  3. Arachnida (Arachne - spider)e.g. Scorpion, spider, tick, mite
  4. Chilopoda (Chilo - lip; poda - appendage)e.g. Centipedes
  5. Diplopoda (Diplo - two; poda- - appendage)e.g. Millipede
  6. Trilobita (an extinct group)
  7. Hexapoda or Insectae.g. Insects.


  1. habit: Many terrestrial and very few aquatic
  2. body:Three-Head, thorax and abdomen
  3. antenna:One pair
  4. visual organs:Both simple eyes and compound eyes (one pair)
  5. locomotion:Three pairs of legs on three thoracic segments and two pairs of wings on meso and metathorax
  6. mouth:Mandibulate - 1 pair
  7. respiration:Tracheal
  8. body fluid:Haemolymph
  9. circulatory system:Heart with ostia
  10. dev.:Metamorphosis
  11. habit:Phytophagous, predators and parasitoides
  12. special str.:Genital structures on 8th and 9th abdominal segments. Brain with proto, deuto and tritocerebrum