CHAPTER

2. 20 CHAPTER Fish

3. History of Fish • Earliest evidence: Fossils from Ordovician period (425 to 500 million years ago) • Slow bottom dwellers with thick, bony plates/scales; poorly developed fins; no jaws (Ostracoderms) • Became extinct ~250 million years ago • From Ostracoderms evolved two groups • Placoderms: ~395 million years ago • Acanthodians: ~410 million years ago • From Acanthodians evolved class Osteichthyes • Sarcopterygii subclass: Only two orders today • Actinopterygii subclass: Now over 20,000 species in 34 orders

4. Characteristics of Fish • Cold-blooded vertebrates that breathe with gills and move and balance with fins • Most covered with scales • Skin has other elements • Glands that produce slimy mucus • Chromatophores that give fish colors • Sensory receptors • Long, folded heart with two chambers • Spherical eyes with no eyelids • Inner ears and taste buds • Digestive system according to diet • Most bony fish have swim bladders

5. Orders of Ray-Finned Fish • Cypriniformes (characins, gymnotid eels, loaches, minnows, suckers) • Siluriformes (catfish) • Atheriniformes (flying fish, half beaks, killifish, needle fish) • Perciformes (cardinal fish, glassfish, and related fish) • Tetraodontiformes (box fish, ocean sunfish, puffers, triggerfish)

6. Orders of Ray-Finned Fish (cont.) • Scorpaeniformes (scorpion fish, sculpins) • Gasterosteiformes (pipefish, sea horses, sticklebacks, trumpetfish) • Mormyriformes (mormyrids) • Osteoglossiformes (bony tongues, freshwater butterfly fish, mooneyes)

7. Major Families of Order Cypriniformes, Suborder Characoidei • Characidae (tetras and characins) • Gasteropelecidae (hatchet fish) • Anostomidae (headstanders) • Hemiodontidae (pencil fish) • Citharinidae (moon fish)

8. Major Families of Order Cypriniformes, Suborder Cyprinoidei • Cyprinidae (minnows and carps) • Gyrinocheilidae (algae eaters) • Cobitidae (loaches)

9. Major Families of Order Siluriformes • Siluridae (glass catfish) • Schilbeidae (three-striped glass catfish) • Mochokidae (upside-down catfish) • Pimelodidae (unarmored catfish) • Callichthyidae (armored catfish) • Loricariidae (sucker catfish)

10. Classification of Order Atheriniformes • Suborder Exocoetoidei • Family Exocoetidae (halfbeaks and flying fish) • Suborder Cyprinodontoidei • Family Cyprinodontidae (killifish or egg-laying tooth carps) • Family Anablepidae (four-eyed fish) • Family Poeciliidae (live-bearers or viviparous top minnows) • Suborder Atherinoidei • Family Atherinidae (rainbow fish or silversides)

11. Suborders of Order Perciformes • Percoidei • Blennioidei • Mastacembeloidei • Anabantoidei

12. Major Families of Suborder Percoidei • Apogonidae (cardinalfish) • Centropomidae (snooks, robalos, and glassfish) • Grammidae (basslets) • Nandidae (leaf fish) • Cichlidae (cichlids) • Pomacentridae (damsel fish, anemone fish) • Monodactylidae (fingerfish) • Toxotidae (archer fish) • Platacidae (bat fish) • Scatophagidae (scats) • Chaetodontidae (butterfly fish) • Labridae (wrasses)

13. Major Families of Suborder Blennioidei • Acanthuridae (surgeons, tangs, and unicorn fish) • Family — Zanclidae (Moorish Idol)

14. Major Family of Suborder Mastacembeloidei • Mastacembelidae (spiny eels)

15. Major Families of Suborder Anabantoidei • Anabantidae (climbing perch) • Helostomatidae (kissing gourami) • Belontiidae (fighting fish and paradise fish) • Osphronemidae (gourami)

16. Classification of Order Tetraodontiformes • Group of saltwater species called triggerfish • Three dorsal spines, second locks upright into the first • Found throughout the world • Widely varied colors, patterns, and shapes • Common species • Undulate or orange-green triggerfish (Balistapus undulatus) • Picasso or white-barred triggerfish (Rhinecanthus aculeatus) • Can be kept in community aquariums but may be aggressive to smaller fish • Maintain water temperature at ~75°F • Feed on chopped meat, shellfish, meat-based sflake foods

17. Classification of Order Scorpaeniformes • Made of lion fish (dragon or turkey fish) • About 14” long • Native to Indo-Pacific and Red seas • Primarily reddish-brown with numerous white bands encircling the body • Long fin rays, poisonous spiny ray • Feeds on live fish or chopped meats, voracious appetite • Maintain water temperature at ~77°F • Can be kept in community aquarium with fish of equal size

18. Classification of Order Gasterosteoidei • Made of sea horses • Vary from black to yellow • Yellow or oceanic sea horse: About 2” long, native to Indo-Pacific marine waters • Have hard body covering, no caudal or anal fins • Swim in vertical position • Prehensile tail anchors to plants and coral • Fairly difficult to keep • House in species aquariums • Maintain water temperature at 77°F • Feed on live foods

19. Classification of Order Mormyriformes • Contains mormyrs and elephant-snout fish • Long-nosed elephant-snout fish (Gnathonemus petersi) • Native to dark, turbid fresh waters of Africa • Grows to 9” long • Dark brown-black with a violet iridescence • Two yellowish-white, irregular, vertical stripes between dorsal and anal fins • Dorsal, anal, and caudal fins edged with white • Lower lip is tool for digging for food on stream bottom • Emit electrical field around body for movement in darkness • Will adapt to community aquarium with dark, secluded hiding places • Maintain water temperature at 75°F • Feed on insects, insect larvae, and worms

20. Classification of Order Osteoglossiformes • Made of fish with long anal fins and reduced or no dorsal fins (often called knife fish) • Move by undulation of long anal fin • African knife fish (Xenomystus nigri) • Grows about 8” long • Primarily light brown with lighter underside • Occasionally rises to surface to swallow atmospheric air • Is peaceful and can be kept in community aquarium with other peaceful fish, dark areas, and vegetation • Maintain water temperature at ~79°F

21. Desired Qualities of Fish Aquariums • Can be made of glass, Plexiglas, acrylic • Size requirements • Tropical freshwater: Maximum 1” of fish/every 10 square inches of surface area • Cold freshwater: Maximum 1” of fish/every 30 square inches of surface area • Marine: Maximum 1” of fish/every 48 square inches of surface area • Location free of drafts, out of direct sunlight, with level surface • Filters/air pumps for dissolved oxygen • Other filter for waste removal • Chemical/biological filters • Protein skimmer • Water heater/thermometer • Lighting • Decorative items

22. Feeding Methods for Fish • Diet according to feeding approach • Small and large fish: Flake foods from fish, fish eggs, wheat, and vegetables and usually added vitamins and minerals • Middle feeders: Small pellets that skin slowly • Large top feeders: Floating fish sticks • Bottom feeders: Sinking pellets • Supplement with other foods • Can feed live foods (water fleas, earthworms, flies, maggots, wood lice) • Supplement with vegetables (chopped or shredded lettuce, chopped spinach leaves, canned peas) • Minced or chopped meat for carnivorous fish • Feed small amounts 2 to 3 times daily

23. Fish Diseases and Ailments • Parasites • White spot • Slime disease • Hole-in-the-head • Velvet disease • White fungus growth • Flukes • Anchor worms • Fish lice • Bacterial diseases • Finrot • Mouth fungus • Neon disease • Tuberculosis • Pseudomonas and Aeromonas

24. Fish Reproduction • Via internal or external fertilization • Egg layers • Egg-scatterers • Egg-buryers • Egg-depositors • Mouth-brooders • Nest-builders • Live bearers