Transcript ZOOPLANKTON - Susquehanna University

ZOOPLANKTON
Diversity of the Heterotrophic
Plankton Community
Major Groups of Zooplankton
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Ciliates
Rhizopods
Rotifers
Cladocerans
Copepods
Ciliate Zooplankton
• Animal-like unicellular heterotrophs.
• All have two different types of nuclei.
• They move and feed by cilia.
Some common ciliates in the
microzooplankton community
• Stentor
• Halteria
• Tintinnida
Rhizopod Zooplankton
• These are amoeboid unicellular heterotrophs
• Most common taxa observed in the
microzooplankton are thecate like Difflugia.
Actinopod Zooplankton
• These are free-floating cells with radiating
axopods. e.g. Actinosphaerium.
Turbellarian Zooplankton
• These are free-living flatworms that live in
stagnant pools and eutrophic lakes. e.g.
Stenostomum
Rotiferan Zooplankton
• Animal heterotrophs that feed by ciliary pads
surrounding the mouth.
• All have a specialized “jaws” called trophi in
the gullet.
• Many are covered by a lorica.
Typical Life Cycle of a Rotifer
Some Rotifers in the Zooplankton
• Keratella
• Polyarthra
• Filinia
More Rotifers
• Brachionus
• Asplanchna
• Conochilus
Annelid Zooplankton
• Oligochaete segmented worm. e.g. Aeolosoma
Arthropod Zooplankters
Most freshwater taxa are Crustaceans
(arthropods with cephalothorax and
abdomen)
– Order Anostraca
– Order Ostracoda
– Order Cladocera
– Order Copepoda
• Suborder Calanoida
• Suborder Cyclopoida
• Suborder Harpacticoida
Anostracan Zooplankton
• Fairy Shrimp
• Clam Shrimp
• Tadpole Shrimp
Ostracod Zooplankters
• Sometimes called seed shrimp. Rarely in the
euplankton.
Cladoceran Zooplankton
Cladoceran Life Cycle
Filter-Feeding Cladocerans
• Holopedium
• Diaphanosoma
• Chydorus
More Filter-Feeding Cladocerans
• Daphnia
• Bosmina
• Moina
Predaceous Cladocerans
• Leptodora
• Polyphemus
Copepod Diversity
• Suborder Cyclopoida
• Suborder Calanoida
• Suborder Harpacticoida
Copepod Life Cycle
Calanoid Copepods
• Diaptomus
• Epischura
• Limnocalanus
Cyclopoid Copepods
• Cyclops
• Macrocyclops
• Megacyclops
Harpacticoid Copepods