Daphnia
Introduction: Daphnia is a large genus comprising over 200 species of small freshwater crustaceans that belongs to the family Daphniidae and the order “Cladocera”. The common name of Daphnia is water flea and this name is due to jerky-flea like swimming movement. Daphnia often live is freshwater bodies of relative different quality including swamps, lakes, streams and rivers.
Description: Daphnia in general are small and may range from as small as 0.5 mm to as long as 5.0 mm in length, sometimes more; and hence some daphnia species can be seen by naked eyes (e.g. Daphnia magna) , while others must are microscopic (e.g. Daphnia pulex). Usually females are larger than males and have a brood chamber under their carapace where eggs are kept.
The uncalcified …show more content…
Feeding habits and role in the food chain: Daphnia feeds mainly on unicellular algae, yeast and bacteria. Upon feeding, Daphnia uses its third pair legs to filter the water allowing the proper food size in while keeping the large particles out. Beating the water with the other sets of legs create water current that brings in additional food.
The feeding habit of Daphnia explains their ecological role as their lower density and consequently less food consumption could lead to algal overgrowth along with possible decline in dissolved oxygen during night. On the other hand, the importance of Daphnia in the food chain is significant as Daphnia is preyed upon by several aquatic organisms such as tadpoles, salamanders, aquatic insects, and many of small fish species. Ultimately, and by the end of the chain, food fish for human consumption could be affected as a result of the negative changes in Daphnia