Transcript Slideshow
Vertebrate Zoology The Fish Classes Fish Classes There are three types of fishes. The classes are based upon the characteristics of those classes. All three classes fall into the Superclass of Pisces. Class Agnatha Class Meaning Examples Lamprey Greek Root Words A – not Gnathos - jaw Lampreys Hagfishes Jawless Fish Hagfish Distinguishing Characteristics: No jaws Cartilage for skeleton Ventral fin absent No scales Pore-like gill openings Jawless Fish Habitat Freshwater lamprey attached to a fish. Marine and Freshwater Species. Usually live as parasites on other species. About 60 Species of jawless fish. Jawless Fish Notice circular mouth with no moveable jaw. Circular mouth. Teeth point in toward the middle. Usually kill the host over time. Class Chondrichthyes Class Meaning White-tipped Shark Greek Root Words Chondros - cartilage Ichthyes - fish Examples Sharks Skates Rays Class Chondrichthyes Leopard Shark Distinguishing Characteristics: Cartilage for skeleton No swim bladder Slits over the gills Class Chondrichthyes Habitat Blue-spotted Stingray Mostly marine. Usually high level carnivores. About 625 species left. Class Osteichthyes Class Meaning Examples Barracuda Greek Root Words Osteon - bone Ichthyes - fish Bass Tuna Minnow Goldfish Class Osteichthyes Four-eyed Butterfly Fish Distinguishing Characteristics: Skeleton is mostly bone. Single gill opening on each side. Swim bladder present. Some have primitive lung. Class Osteichthyes Habitat Gray Snappers Marine & Freshwater. All types of feeding habits. About 18,000 species of bony fish distributed all over the globe. Physiological Activities of Pisces Nutrition The types of nutrition varies tremendously when you consider all the species. Sharks Feeding while another species got lucky! Physiological Activities of Pisces Gas Exchange All species use gills. Some species have lungs as well as gills for temporary use while out of water. African Lungfish use lungs to breathe as they move from a water hole that is drying out to another one with more water. Physiological Activities of Pisces Support and Locomotion Cartilage or bone, depending on the species. Swimming is main method of locomotion. Big Skate swimming. Physiological Activities of Pisces Support and Locomotion Nurse Shark resting on bottom. Swim bladder allows some species to float. Have segmental muscles along sides. Produces the zigzag swim motion of most fish. Physiological Activities of Pisces Sensory and Nervous. Reproduction Skate egg case, also called a mermaid’s purse. Well developed eyes and smell. Lateral Line in most species. Acts like touch. Most use external fertilization and development. Important Terminology Coelacanth Fish that was believed to be extinct Has strong fins for “walking” on the bottom Coelacanth Important Terminology Fin Rays Support structure in fins. Fins Control and swim devices. Types: Queen Triggerfish Dorsal, caudal, lateral, pectoral, pelvic, & anal. Important Terminology Scale Small, hard outer covering for protection. Gill Gas exchange devices for all fish species. Scale Types Fish Gill Function Important Terminology Swim Bladder Mudskippers use their lungs to breathe when they move out onto mud flats to hunt for insects and small crustaceans. Air-filled sac that provides buoyancy. May have evolved to act as lungs in fish species that went on to become amphibians. Important Terminology Segmental Muscles Muscles along the sides of most fish are divided into segments. Alternating contractions from side to side produce swimming motion. Important Terminology Lateral Line Hammerhead Swimming Sensory devices along the sides of most fish species. Serves as “touch”. Try to catch a fish in water with your bare hands! General Fish Anatomy Mouth General Fish Anatomy Eye General Fish Anatomy Backbone General Fish Anatomy Anterior Dorsal Fin General Fish Anatomy Posterior Dorsal Fin General Fish Anatomy Scales General Fish Anatomy Caudal Fin General Fish Anatomy Heart General Fish Anatomy Stomach General Fish Anatomy Pectoral Fin General Fish Anatomy Intestines General Fish Anatomy Swim Bladder General Fish Anatomy Anal Fin Question #1 Proper Fish Classes Agnatha, Chondrichthyes, Osteichthyes Common Characteristics Live in Water. Gills for breathing. Question #2 Cartilage for skeleton. Gill slits or pores for breathing. Bony fish have a single opening. Do not have a swim bladder. Question #3 Allowed for more refined movements (better control). No longer had to rely on caudal fin. Could now hover and hide from prey, allows for surprise ambush.