World Families II: Marine pelagic and tropical freshwater fishes

1. World Families II:Marine pelagic and tropical freshwater fishes November 27, 2012

2. Marine Pelagic Fishes • Of >25,000 known fish species, ~15,000 are marine • Majority are associated with seafloor, but a diverse community also occupies open water pelagic zone • More mobile and wide ranging than benthic fishes • Vary from small, schooling fish to large predators

3. Family List Engraulidae: anchovies Exocoetidae: flying fishes Megalopidae: tarpons Scombridae: tunas Sphyraenidae: barracudas Sphyrnidae: hammerhead sharks Istiophoridae: billfishes

4. Engraulidae: anchovies • Mouth inferior, very large, upper jaw produced • Gill rakers often numerous • Silver stripe down flanks • Abdominal scutes in OW species • Most species <15cm

5. Exocoetidae: flying fishes • Name means “outside of home” • Unusually large pectoral fins, some species also with large pelvic fins (four-winged appearance) • Jaws relatively short • Caudal fin deeply forked, upper lobe shorter http://www.youtube.com/watch?v=8nEwte-x-iw

6. Megalopidae: tarpons • Large silvery fishes of tropical and subtropical waters • Single dorsal fin without spines • Fusiform, compressed body • Lower jaw prominent • Filamentous last dorsal ray

7. Scombridae: tunas • Body elongate and fusiform • Snout pointed, premaxilla beaklike • Mouth large with variable teeth • Two dorsal fins, separate • 5-12 finlets behind 2nd dorsal and anal • Caudal deeply forked

8. Sphyraenidae: barracudas • Elongated body • Large-mouthed with lower jaw projecting forward bearing strong fanglike teeth • Upper jaw non-protractible (large prey) • Low pectoral fins, dorsal fins far apart

9. Sphyrnidae: hammerhead sharks • “sphyrna” = hammer • Head laterally expanded, with eyes and nasal openings wide-set (compared to other sharks) • Blades presumed to increase sensory capabilities • No spiracle • Viviparous

10. Istiophoridae: billfishes • Name means “sail carrier” • Premaxilla and nasal bones extremely elongated, forming spearlike bill or rostrum • Very narrow pelvic fins • Median keel on caudal peduncle

11. Tropical Freshwater Fishes

12. Tropical Freshwater Fishes • Tropical aquatic habitat includes some of the world’s largest rivers, e.g., the Amazon, Madeira, Mekong, Orinoco, Negro, and Zaire • Tropical freshwater fishes threatened by rainforest destruction, damming of rivers, pollution, erosion, pet trade, introduction of exotics

13. Family List *Cichlidae: cichlids Gasteropelecidae: freshwater hatchetfishes Polypteridae: bichirs Potamotrygonidae: freshwater stingrays Toxotidae: archerfishes Channidae: snakeheads Loricariidae: sucker-mouthed armored catfishes Protopteridae: African lungfishes Ceratodontidae: Australian lungfishes *Osteoglossidae: arowanas Arapaimidae: arapaima and relatives *Lepisosteidae: gars *will not be tested

14. *Cichlidae: cichlids • Body shape variable, mostly moderately deep and compressed • Interrupted lateral line in most • Breeding activities highly organized • Mouthbrooders, substratebrooders • Highly speciose and widely distributed • Hippo cleaners *will not be tested

15. Gasteropelecidae: freshwater hatchetfishes • Enlarged, strongly convex muscular pectoral girdle • Single dorsal fin, adipose fin present in larger species • Jumping capabilities thanks to long pectorals • Found in Central and South America • Name means “stomach axe”

16. Polypteridae: bichirs • Name refers to series of finlets on dorsum • Body elongated or anguilliform with thick rhombic/ganoid scales • Symmetric caudal fin • Pectorals with lobed base • Some species without pelvics

17. Potamotrygonidae: freshwater stingrays • Name means “river,” “three points” • Med to large batoids, with short stout tail • Dorsal surface usually covered with thorns or denticles • Most with spotted/colorful dorsum • Outline round

18. Toxotidae: archerfishes • Compressed, deep body • Large eyes • Mouth long with lower jaw longer • Anal fin with three spines • Spiny and soft dorsal continuous • archerfish on BBC

19. Channidae: snakeheads • 2 genera (1 Asian 1 African) • Elongate body • Lower jaw protruding • Long dorsal and anal • No spines in fins • Introduced in CA, MD, and Southeast

20. Loricariidae: armored catfishes • Body covered with bony plates • Ventral sucker mouth, some with barbels • Adipose fin absent or, when present, with spine at front

21. Protopteridae: African lungfishes • Body moderately elongate • Threadlike pectorals and pelvics • Able to survive dry spells by aestivation (reduced metabolism, burrowed in mud and enveloped in mucus cocoon) • lungfish aestivation

22. Ceratodontidae: Australian lungfishes • Stout, elongate body with flattened head and small eyes • Large bony scales cover body • Fins flipper like • Caudal fin paddle shaped

23. Arapaimidae: bonytongues • 2 species: Arapaima and Heterotis • Heterocercal tail • Torpedo shaped body, large scales • Long anal and dorsal set far back • Pectorals low, pelvics set far back • Air breathers

24. *Osteoglossidae: arowanas • Elongate, slender body with large scales • Barbels present at symphasis of lower jaw • Large mouth with markedly oblique gape • Name means “bony tongue” *will not be tested

25. *Lepisosteidae: Gars • Atractosteustropicus– tropical gar • Distribution from Mexico to Costa Rica • Aquacultured as food fish; also overfished *will not be tested (on world families section