Glossary Amphipod- Of the order Amphipoda,class Crustacea, including freshwater shrimps or side swimmers because their body is flattened from side to side Anadromous- Fish that migrate from saltwater to spawn in freshwater (Sea) Anemone- Numerous, usually solitary, brightly colored, anthozoan polyps; of the Order Actiniaria Annelid- Elongated, segmented invertebrate; including earthworms and leeches; of the Phylum Annelida Arthropod- Having a segmented body, jointed appendages and a chitinous exoskeleton; Including crabs, insects, spiders, etc.; of the Phylum Arthropoda Bathypelagic- Below mesopelagic zone; at 1000- 4000 m depth Benthic- Relating to the seabed or riverbed Benthopelagic- Lives in the water column but is associated with the sea floor Brackish- Somewhat salty Catadromous- Fish which spend most of their life in freshwater and migrate to the sea to breed Chaetognath- Arrow-worms, small planktonic wormlike marine organisms having curved bristles on either side of the head for seizing prey; of the Phylum Chaetognaths Chironomid- Small two winged flies called midges that lack piercing mouthparts; of the Family Chironomidae Cladoceran- Tiny, mainly freshwater branchiopod crustaceans, including water fleas; of the Order Cladocera Coelenterate- Radially symmetrical invertebrate, including corals, sea anemones, jellyfishes and hydroids; of the phylum Cnidaria Copepod- Minute marine species found in plankton, important food for fishes; of the subclass Crustacea Ctenophore- Comb jellies; invertebrate with rows of ciliary combs covering the animal's surface; of the phylum Ctenophora Decapod- Crustaceans including shrimps, lobsters and crayfish; of the order Decapoda Demersal- Close to, or lying on the bottom but not attached or buried Diatom- Planktonic unicellular or colonial algae with skeletons made of silica Dioecious- Species in which sexes are always separate (opposite of hermaphroditic and monoecious) Echinoderm- Invertebrate with penta-radial symmetry, often covered by a hard or spiny skin, including sea urchins and sea cucumbers; of the phylum Echinodermata Ectoparasite- A parasite living on the exterior of its host Elver- A developmental stage in the eel,Anguilla life cycle between leptocephali and adult, in which a remsemblance to adults occurs, as well as an upriver migration Ephemeroptera- Mayflies, freshwater insects Epipelagic- Uppermost (normally photic) layer of the ocean; at 0- 200 m depth Euphausiid- Small, usually luminescent malacostran crustaceans resembling shrimps Foraminifer- Large, chiefly marine rhizopod protozoans usually having calcareous shells often perforated with minute holes for protrusion of slender pseudopodia; of the Order Foraminifera Gametogenesis- The production of sperm and egg cells Gammarid- A family of the Order Amphipoda Gastropod- Snails with spiral or simple shells of the class Gastropoda Gorgonian- Colonial anthozoans with a usually horny and branching axial skeleton; of the Order Gorgonacea Hydrozoan- Simple and compound polys and jellyfishes, including stinging corals and Portugese man of war; of the Class Hydrozoa Isopod- Small, sessile-eyed crustaceans similiar to amphipods but flattened from above of the Order Isopoda include sand and beach fleas and pond louse Leptocephali- A developmental stage in the Anguilla life cycle following the egg, when the Organism floats from the birth site toward freshwater Macrourid- Grenadier fish, having an elongate tapering body and a compressed pointed tail; of the Family Macrouridae Mesopelagic- Between epi- and bathypelagic zones; at 200- 1000 m depth Nyctoepipelagic- Migrating from deeper waters to the epipelagic zone at night Ostracod- Small, active, mostly freshwater crustaceans having a carapace covering and seven pairs of appendages; of the Subclass Ostracoda Ovoviviparous- "Live-bearing" fish, eggs are held within the body of the female where the development of the embryo takes place Oviparous- Producing eggs that develop and hatch outside the female's body Pelagic- Associated with middle depths of bodies of water; at 0- 200 m depth Polychaete- Segmented worms, including bloodworms and sea mice; of the Phylum Annelida Polyp- A coelenterate having a hollow cylindrical body closed at one end and opened at the other with a central mouth surrounded by tentacles armoured with nematocysts Protandrous- Sequential hermaphrodite, in which the organism is first a male and later a female Protogynous- Sequential hermaphrodite, in which the organism first functions as a female and later as a male Pteropod- Molluscs having the anterior lobes of the foot expanded into broad thin winglike swimming organs Salp- Transparent, barrel-shaped or fusiform free-swimming tunicates Substrate- Surface on which an organism feeds Substratum- A surface of seabed, lakebed or riverbed Tunicate- Marine chordate animals with a thick covering layer, including sea squirts; of the Subphylum Urochordata Viviparous- Producing free-swimming young, rather than laying eggs