Lecture 9. Monday, September 15, Details on basal Actinopterygiians a. bichirs - Polypteriformes b. sturgeon & paddle fish - Acipenseriformes c. gar - Semionotiformes d. bowfin - Amiiformes 2. Review material to date.

Class Actinopterygii - the ray-finned fishes Polypteriformes Acipenseriformes Semionotiformes Amiiformes Teleostei Semiontiformes = Lepisosteiformes

Order Polypteriformes - bichirs

Polypteriformes

Order Polypteriformes - bichirs 5 to 18 separate finlets- each with a spine and soft rays Unique characters

Order Acipenseriformes - sturgeons and paddlefish Polypteriformes Acipenseriformes Semionotiformes Amiiformes Teleostei

Family Acipenseridae - sturgeon

link to Carol’s website

Family Acipenseridae

= grave conservation situation, several species near extinction

Family Acipenseridae Sturgeons are the largest fishes found in freshwaters beluga sturgeon -27 ft, 1,800 lbs. recreational fishery for more common species still a viable industry

sturgeon video Lwed8http:// Lwed8

Family Polyodontidae - paddlefishes

Family Polyodontidae

Snout not developed in juveniles

Family Polyodontidae Two species Polyodon spatula - Mississippi River Drainage of eastern United States Psephurus gladius-China, Yangtze Drainage

Family Polyodontidae Polyodon spathula - biology Filter feeder, zooplankton, mouth non- protrusible

Class Actinopterygii - the ray-finned fishes Polypteriformes Acipenseriformes Semionotiformes Amiiformes Teleostei

Family Lepisosteidae Fossils

Order Semiontiformes - gar

Range

Order Semiontiformes - gar Heterocercal tail

Order Semiontiformes - gar Vascular air bladder

Order Semiontiformes - gar habitat

Family Lepisosteidae - biology Spawn in late spring over shallow vegetated areas Female accompanied by multiple males, eggs broadcast over substrate Eggs are large, adhesive, & poisonous. Adhere to vegetation Larvae hatch with adhesive disk at tip of lower jaw, attach to vegetation until yolk sac is absorbed

Family Lepisosteidae - biology Reach maturity at 3 yrs, can live up to 20 yrs. Piscivores - lie-in-wait predators Most species average ft. in size, alligator gar can reach 10 ft.

Family Lepisosteidae - biology Of seven known species, four known to occur in Illinois

spotted gar eating a fish

Order Amiiformes One extant family, Amiidae one extant species - Amia calva

Order Amiiformes Amia calva Long dorsal fin, aids in propulsion Heterocercal tail

Order Amiiformes

Amia calva - biology Life span ~10 years Can reach ft. in length

Group Activity #1 -Draw the phylogenetic tree & distinguishing traits for: group a - Myxiniformes, Gnathostomata, Chondrichthyes, Teleosts group b - Petromyzontiformes, Elasmobranchii, Holocephali, Sarcopterygii, Actinopterygii group c - Elasmobranchii, Holocephali, Sarcopterygii, Teleosts group d - Myxiniformes, Petromyzontiformes, Chondrichthyes, Osteichthyes

Group Activity #2 - Rotate at least 2 nodes of the tree and draw it again. Group Activity #3 - Design a dichotomous key that would allow one to distinguish these groups For example... Step 1 - lacks vertebrae --> Myxiniformes if not --> go to step 2 Step 2 - lacks jaws --> Petromyzontiformes if not --> go to step 3

Group Activity Number 4: Describe the general pattern in the evolution of the following: group a - evolutionary transition from jawless to jaws group b - evolutionary transition from no paired fins to paired fins group c - a possible explanation for the evolution of reproduction/offspring development in Elasmobranchii group d - evolution of scales Group Activity #5: For the same groups... describe the implications of these evolutionary transitions.

Group Activity #6 - Describe the evolutionary transitions of the following: a) evolution of caudal fin shapes. b) evolution of lungs/swim bladders. c) evolution of the role of the maxilla and pre-maxilla in eating. d) evolutionary loss of the spiral valve What are the possible implications of these changes for fishes?

For each of the following taxa, list at least 3 details about their biology : group 1: hagfish, Acanthodii, hammerhead, skates, basking shark bichirs, black carp group 2: lampreys, chimaeras, manta ray, electric rays, Coelacanth, sturgeon, common carp group 3: Ostracoderms, whale shark, sting ray, great white, Australian lungfish, bowfin, grass carp group 4: Placoderms, thresher shark, sawfish, megamouth, S.A. & African lungfish, paddlefish, silver & bighead carp