David Fleetham / Great barracuda (Sphyraena barracuda) with three parasitic Copepods at end of upper jaw. Hawaii.

Wild Wonders of Europe / Pitkin / Dusky grouper (Epinephelus marginatus)with a few fish lice (parasitic copepods) are visible near its nostril, Cala di Grecu, Lavezzi Islands, Corsica, France, September 2008 WWE BOOK.

Solvin Zankl / Marine Planktonic Copepod {Gaussia princeps} female, deepsea, Atlantic ocean

Solvin Zankl / Deepsea marine planktonic Copepod {Euchirella sp} Atlantic ocean

Solvin Zankl / Deepsea marine planktonic Copepod (Sapphirina sali) Atlantic ocean, Digital focus stacking

Doug Perrine / Parasitic copepods {Copepoda sp.} on snout of Hammerhead shark {Sphyrnidae sp.} Bahamas

Alex Mustard / A larval mantis shrimp (Stomatopoda), copepods and more plankton aggregate at night, in open water. Anilao, Batangas marine protected area, Luzon, Philippines. Verde Island Passages, Tropical West Pac...

Nick Hawkins / Live copepods (Calanus finmarchius) displayed on a microscope slide and photographed at the Bedford Institute of Oceanography, in Halifax, Nova Scotia, Canada.

Nick Hawkins / Live copepods (Calanus finmarchius) displayed on a microscope slide and photographed at the Bedford Institute of Oceanography, in Halifax, Nova Scotia, Canada.

Nick Hawkins / Live copepods (Calanus finmarchius) displayed on a microscope slide and photographed at the Bedford Institute of Oceanography, in Halifax, Nova Scotia, Canada.

David Fleetham / Parasitic Copepod (Copepoda) on Whip coral goby (Bryaninops amplus), on whip coral, (Junceella fragilis), Indonesia.

Will Watson / Natural oil released from dead Copepods under anoxic conditions on a back marsh, Upton Warren flash pool, Worcestershire, England, August 2017.