BI256 Lecture Notes - Lecture 19: Ostracod, Bivalvia, Seta
Document Summary
Lecture 19 arthropoda crustaceans part 1 - chapter 20 feb 17th. Commonly called (cid:862)mussel shrimp(cid:863) or (cid:862)seed shrimp(cid:863) with 6000 known species found worldwide in both marine and freshwater habitats. Enclosed in a bivalve carapace ranging from 0. 25-8. 0 mm long. Feeding and locomotion are mostly by head appendages. Most are benthic or climb on plants, but some are planktonic and burrowing while others are parasitic. Huge collective biomass (billions of tons) in marine and freshwater. Retain a single nauplius (maxillopodan) median eye in adults. Most abundant animals in the world are members of the copoped genus calanus cyclops and diatomus important elements of freshwater plankton. Some free living copepods are intermediate hosts of human parasitic tapeworms and nematodes. Parasitic forms highly modified and reduced with unusual metamorphoses. Includes barnacles in order thoracia and three orders of burrowing or parasitic forms. Adults are sessile and attach directly (acorn barnacles) or by a stalk (goose barnacles)
