Class Clitellata
Phylum Annelida Class Clitellata
Maria Erika Victoria V. Soriano Zoology Summer 2013
PHYLUM ANNELIDA
¡ The segmented worms ¡ Bilaterally symmetrical ¡ Possesses at least one pair of chitinous bristles called setae or chaetae ¡ Exhbits metamerism ¡ Epidermis secretes a protective cuticle that remains permeable to both water and gases; thus, annelids are restricted to moist environment ¡ Septa separates the annelid segments from each other ¡ All are very similar in appearance and strucuture
¡ Both internally and externally
PHYLUM ANNELIDA
¡ Doesn’t possess skeletal material ¡ Lives in tubes, muds, and sand grains ¡ All have closed circulatory system ¡ They reproduce sexually
¡ Separate sexes
¡ Functional Hermaphrodites
CLASS CLITELLATA
¡ “girdle worms” ¡ Earthworm and leeches ¡ Defined by having:
¡ No parapodia ¡ Reduced or absent setae ¡ Hermaphroditic ¡ Possesses clitellum
¡ Clitellum – cylindrical glandular region of the body at segments 32-37 that place important role in reproduciton
¡ Secretes a cocoon within which embryos develop ¡ Also secretes mucus that assists in tranferring sperm between individuals ¡ Produces albumen which serves as a food source for the embryos as they develop within the cocoon
CLASS CLITELLATA
SUBCLASS OLIGOCHAETA SUBCLASS HIRUDINEA
SUBCLASS OLIGOCHAETA
¡ Mostly found in freshwater or terrestrial habitat, very few are marine ¡ Includes the earthworms ¡ Lacks sensory structures such as eyes and tentacles ¡ Prostomium – anterior most region of the body ¡ Scavengers ¡ No specialized respiratory organ ¡ Locomotion: Peristaltic Waves ¡ Reproduction: ¡ All oligochaetes are hermaphroditic ¡ External fertilization ¡ Freshwater oligochates undergo asexual reproduction through transverse division of the body
SUBCLASS HIRUDINEA
¡ Mostly found in freshwater or terrestrial habitat, very few are marine ¡ Includes leeches ¡ Parasites ¡ Subclass defined by
Maria Erika Victoria V. Soriano Zoology Summer 2013
PHYLUM ANNELIDA
¡ The segmented worms ¡ Bilaterally symmetrical ¡ Possesses at least one pair of chitinous bristles called setae or chaetae ¡ Exhbits metamerism ¡ Epidermis secretes a protective cuticle that remains permeable to both water and gases; thus, annelids are restricted to moist environment ¡ Septa separates the annelid segments from each other ¡ All are very similar in appearance and strucuture
¡ Both internally and externally
PHYLUM ANNELIDA
¡ Doesn’t possess skeletal material ¡ Lives in tubes, muds, and sand grains ¡ All have closed circulatory system ¡ They reproduce sexually
¡ Separate sexes
¡ Functional Hermaphrodites
CLASS CLITELLATA
¡ “girdle worms” ¡ Earthworm and leeches ¡ Defined by having:
¡ No parapodia ¡ Reduced or absent setae ¡ Hermaphroditic ¡ Possesses clitellum
¡ Clitellum – cylindrical glandular region of the body at segments 32-37 that place important role in reproduciton
¡ Secretes a cocoon within which embryos develop ¡ Also secretes mucus that assists in tranferring sperm between individuals ¡ Produces albumen which serves as a food source for the embryos as they develop within the cocoon
CLASS CLITELLATA
SUBCLASS OLIGOCHAETA SUBCLASS HIRUDINEA
SUBCLASS OLIGOCHAETA
¡ Mostly found in freshwater or terrestrial habitat, very few are marine ¡ Includes the earthworms ¡ Lacks sensory structures such as eyes and tentacles ¡ Prostomium – anterior most region of the body ¡ Scavengers ¡ No specialized respiratory organ ¡ Locomotion: Peristaltic Waves ¡ Reproduction: ¡ All oligochaetes are hermaphroditic ¡ External fertilization ¡ Freshwater oligochates undergo asexual reproduction through transverse division of the body
SUBCLASS HIRUDINEA
¡ Mostly found in freshwater or terrestrial habitat, very few are marine ¡ Includes leeches ¡ Parasites ¡ Subclass defined by