![](/wp-content/uploads/2021/03/abstractheadergraphic2009.gif)
Meeting Abstract
S2.2 Sunday, Jan. 4 The five wonders of the parasitic Copepoda HO, J.-S.; California State Univ., Long Beach jsho@csulb.edu
Although Copepoda is not the largest group of Crustacea, it embraces the highest number of symbiotic forms among Crustacea. They live on/in every major group of organisms found in the aquatic environment. Judging from the high degree of morphological modification of the oldest known fossil of Copepoda, Kabatarina pattersoni Cressey & Boxshall, a parasite found on the gills of a fossil teleost fish, Cldocycls gardneri Agassiz, preserved in calcareous nodules of Lower Cretaceous in Brazil, copepods must have lived in close association with aquatic animals for long, long time; perhaps, long before the Age of Dinosaurs. With such long history of association, symbiotic copepods today exhibit certain unusual traits in their way of living. While many traits are rarely seen in their free-living peers, some traits are so unusual that they are not even known in other metazoans like them leading a parasitic mode of life. To illustrate such unusual traits, the following five wonders are selected for discussion: 1) occurrence in mesoparasitism, 2) development of an enigmatic attachment organ and switching appendages, 3) specificity in microhabitat, 4) mysterious sexuality with two types of male, and 5) ignorance of host’s immune recognition and attack.