ANNELIDS INFORMATION

1. Different species of
Annelids
By NOMAN KHAN

2. Phylum Annelida
• Annelida is a latin word which means ring so these
worms are also called ring worms.
• There are about 15000 species.
• They are triploblastic ,coelomate and bilaterally
symmetrical.
• locomotory organs are parapodia or chaetea /setae
(small hair like structures)
• Excretion occurs through nephridia.

3. • They have closed circulatory system and no
respiratory organ . ( general surface/gills).
• They are hermaphrodite.
• This phylum have 3 classes.
• 1)Class Polychaeta
• 2)Class Oligochaeta
• 3)Class Hirudinae

4. Class polychaeta
• Poly means many and chaeta maens seta so they
• have many chaeta .
• This class includes Neries and Sabella species .....

5. Neries

6. Neries
• They are found in marine water.
• Their body is elongated and metamerically
segmented.
• Their head is distinct called prostium which possess
eyes tentacles,antennae and bristles or palps.
• Sexes are separate and fertilization is external.
• Locomotion takes place by parapodia.

7. • Resiration occur
through gills under
parapodia .

8. Class Oligochaeta
• Oligo maens few and chaeta means seta so they
have few chaeta or setae ..
• This class include earthworm

9. Earthworm /pheritema posthuma

10. Earthworm
• An earthworm is a tube shaped segmented worm.
• It is found either in soil on soil surface .
• It is nocturnal and feed upon small food particles
and organic matter.
• Its body is metamerically segmented (about 100 to
several segments)......

11. Earthworm
• Locomotion take place by setea annd paapodia is
absent.
They are hermaphrodite...
They are segmented metamerically externally by
transverse grooves and internally by tansverse
muscular partitions called septae into a number of
divisions called somites,metameres or rings.

12. Class Hirudinea
• The members of this class do not have any cheata
...
• Leech are included in this class

13. Leech /Hirudinaria

14. Leech
• It lives on the outer surface of their host and are
ecto parasites
• Its body consists of definite number of segments i-
e 34 .
• Body is elongated and flattened.

15. • They donot have chetae or appendages ..
• Reproduction is sexual.
They are hermaphrodite .
They are blood suckers
They are used in treatment as tbey secrete anti
clotting enzyme Hirudin during blood sucking.

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17. • Thank you ............