Daphnia

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CLASSIFICATION

PHYLUM ARTHROPODA (Jointed appendages).

SUB-PHYLUM CRUSTACEA (Biramous appendages).

CLASS: BRACHIOPODA (Trunk appendages as gills).


COMMENTS:

• Commonly called 'water flea'.

•Microscopic, attain a length of about 2 mm.

• Body is oval & laterally compressed with a ventral beak on head & sharp caudal spine.

•Head bears reduced uniramous antennules, & two very large biramous antennal.

•A thin bivalved carapace covers the body except the head.

• Carapace is transparent.

• Sessile compound eyes are united to large structure.

• 5 pairs of thoracic appendages food an efficient food gathering organ.

• Abdominal appendages are absent.

• Sexes are separate.

• Brood pouch present in female but absent

in males. Development of eggs take place

in brood pouch.



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