sub class actinopterygii the ray-finned fishes
DESCRIPTION
Sub class Actinopterygii The ray-finned fishes. Other Orders - Tetraodontiformes. Pufferfish, burrfish and porcupinefish - mostly marine, but a few freshwater species Tetraodotoxin or tetrodoxin. Other Orders - Tetraodontiformes. Fugu. Tetraodotoxin or tetrodoxin. - PowerPoint PPT PresentationTRANSCRIPT
SubSubclass Actinopterygiiclass ActinopterygiiThe ray-finned fishesThe ray-finned fishes
Other Orders - Tetraodontiformes
– Pufferfish, burrfish and porcupinefish - mostly marine, but a few freshwater species
– Tetraodotoxin or tetrodoxin
Other Orders - Tetraodontiformes
– Tetraodotoxin or tetrodoxin
Fugu
Other Orders - Tetraodontiformes
Ocean Sunfish – 3 species
Most fecund vertebrate - >300 million eggs
Other Orders – Pleuronectiformes - flatfishes
• Benthic, mostly marine - both eyes on same side of head
• Eyes on both sides as juveniles, one migrates to other side as individual matures
• Both left and right eyed families
Other Orders - Pleuronectiformes
• 570 species - flounder, soles, halibut
Other Marine Vertebrates
Class Reptilia Order Testudines - Sea turtles Family Dermochelyidae Family Cheloniidae - 1 species - 6 species
Other Marine Vertebrates – sea turtles
Family Dermochelyidae Family Cheloniidae
- all listed or protected by at least one international conservation organization
- usually have both herbivorous and carnivorous life stages
- associated with coral reefs during two life-stages 1) immature (growth) and adult foraging (before reproductive activities)
2) pre-nesting by females
Other Marine Vertebrates – sea turtles
Family Dermochelyidae Family Cheloniidae
Generalized life history
Other Marine Vertebrates – sea turtles
Family Dermochelyidae
- largest turtle in the world – up to 6 ft - only turtle that is functional endotherm - can raise body
temperature 18 C above ambient water temp- can dive to 1230 m (4,000 ft)
- diet is 90% jellyfish
Leatherback
Other Marine Vertebrates – sea turtles
Family Dermochelyidae - Leatherback esophagus is lined with spines to prevent jellyfish from
swimming out
Other Marine Vertebrates – sea turtles
Family Dermochelyidae - Leatherback body temperature is maintained above surrounding seawater - counter-current blood flow system in flippers - thermal inertia - large size and thick layer of fat under skin
counter-current blood flow
Other Marine Vertebrates – sea turtles
Family Cheloniidae –
Flatback TurtleLoggerhead Turtle
Hawksbill Turtle
Olive Ridley Turtle
Other Marine Vertebrates – sea turtles
Family Cheloniidae
Kemp’s Ridley Turtle - rarest of the marine turtles
- ~2000 nests in one location
Other Marine Vertebrates – sea turtles
Family Cheloniidae
Green Turtle – most common marine turtle- 20 nesting locations
Family Dermochelyidae Family Cheloniidae
Sex DeterminationIn most turtles, sex is determined by the incubation temperature of the nest. This is called temperature dependent sex determination (TSD). There are three major patterns of TSD.
A. Males at high tempsB. Males at low tempsC. Males at intermediate temps
Conservation of marine turtles
- By-catch
- Poaching/Products
- Predation
- Disease
- Pollution
Conservation of marine turtles
- By-catch: both long-line fishing and shrimp fishing/trawling
TEDs
Conservation of marine turtles
- Poaching - turtle products
Conservation of marine turtles
- Predation
Conservation of marine turtles
-Disease - fibropapilloma tumors
herpes type virus – no known cause
Conservation of marine turtles
-Pollution•Light plastics
Other marine reptiles
Order Squamata Family Elapidae - sea snakes (also includes cobras,
kraits, coral snakes)
- ~ 70 species are marine - all marine species are limited to Indian and Pacific Oceans - most species are fully aquatic, never leaving the water - strong neurotoxins, but rarely aggressive
Olive seasnake
Yellow-bellied seasnake
Other marine reptiles
Family Elapidae -
Venom delivery mechanism
Proteroglyphous- a single, fixed, hollow fang on the anterior of each maxilla.
Other marine reptiles
Family Elapidae - toxicity
Venom toxicity - The most common measure of toxicity is the LD-50.
This is the amount of a substance that is required
to kill 50% of the test animals (e.g. mice or rats) in one dose.
Name LD-50(mg/kg) RangeBox Jellyfish 0.02 -0.04 ? South Pacific/AustraliaTaipan 0.025 AustraliaBrown Snake 0.0365 AustraliaYellow Sea Snake 0.067 Pacific OceanChinese Cobra 0.29 ChinaPufferfish 0.334 tropical oceansTimber Rattlesnake 5.1 North America
Marine Mammals – Class Mammalia
• Mammals first appear in fossil record about 220 mya
• at least three lineages have invaded the marine environment
Carnivora 1 species
Pinnipedia 34
Sirenia 4
Cetacea 90
Marine Mammals – Class Mammalia
Most important adaptations
- conservation of body heat – large size, blubber
- extremely efficient at absorbing/conserving oxygen
- carry higher conc.of red blood cells, more hemoglobin in blood - muscles carry more myoglobin
Marine Mammals – Class Mammalia
- extremely efficient at absorbing/conserving oxygen
Up to 30 min. Up to 30 min. Over an hour4-5 min.
Marine Mammals – Class Mammalia
Carnivora Pinnipedia
Found in cold waters
Tail is modified pair of hindlimbs
All are carnivorous
Most reach large body sizes – conform to Bergmann’s Rule
Marine Mammals – Class Mammalia
Bergmann’s Rule (1847) – within a given group of organisms, those with larger body sizes will be found at higher latitudes
Elephant seal – 20’California Harbor seal – 6’
Larger animals have a lower surface area to volume ratio – radiate less heat
dugong manatee
Found in warm waters, fully aquatic
All are the only herbivorous marine mammals
Have lost hindlimbs entirely
Three manatee species occur in Atlantic Ocean coastal areas - Dugong occurs from East Africa to western Pacific islands
All four species of conservation concern, all listed as CITES species
CITES = Convention on the International Trade in Endangered Species
Stellar’s Sea Cow
Commander Islands
Described by science in 1741Extinct by 1768
Marine Mammals – Class Mammalia
Cetaceans
Mostly found in colder waters – warmer waters for reproduction
Most complete transformation to aquatic life
• very streamlined bodies• loss of hindlimbs• strong convergent evolution
Marine Mammals – Class Mammalia
Cetaceans
Most complete transformation to aquatic life
• very streamlined bodies – speeds up to 40 mph • blowhole at top of head – some species can empty and refill lungs in 2 second
• most efficient use of oxygen
•Best developed system of echolocation
Marine Mammals – Class Mammalia
CetaceansTwo groups – Baleen Whales Toothed Whales18 species 72 species