Phylum Chordata

Subphylum Craniata (Vertebrata)

Phylum Chordata, Subphylum Vertebrata (Craniata)

• Increase in brain size & sensory apparati• Derivation of neural crest• Enclosure of anterior neural tube in cartilage/bone

(neural crest derivative)• Subsequent derivation of cartilaginous vertebrae,

bony jaws & cranium• Ossification of skeleton & derivation of appendicular

skeleton

• Two superclasses – Agnatha – without jaws– Gnathostomata – mouth with jaws

Cranium Formation

Vertebrae

Pharyngeal Slits: From Feeding to Respiration

Elaboration of Sensory Systems

Subphylum (group)

superclass

Vertebrate Cladistics

superclass

Phish Phylogeny

Class Myxini - Hagfish

Hagfish Feeding

Class Cephalaspidomorphi

Lamprey

Ammocoete Larvae of Lamprey

• Filter feeders using pharyngeal slits

Lamprey

Lamprey Feeding

Lamprey Wound

The terrifying development from the terrifying

pharyngeal pouches

Development of Jaws

Class Chondrichthyes – Cartilaginous Fish

Class Chondrichthyes Subclass Elasmobranchii

• sharks & skates & rays• Skates

– Fleshy tail, 2 dorsal fins, sometimes caudal fin

– Lay egg case (mermaid’s purse)• Rays

– Narrow tail without fins, with spines

Class Chondrichthyes Subclass ElasmobranchiiCaudal fin

Unique Sensory Structures

Chondrichthyes Anatomy

Rostrum

Subclass Holocephali – Chimeras

Chondrichthyes Reproduction

• Internal fertilization– Males have claspers between

pelvic fins• Reproductive modes

– Oviparous• Fertilized egg is laid

– Ovoviviparous• Egg develops within female and

living young are born• No placenta or placental structures

– Viviparous• Embryos develop within female

and living young are born• Some placenta-like structures

of maternal origin

Group Osteichthyes – bony fish• Class Actinopterygii – ray-finned fish

– subclass Neopterygia– subclass Chondrostei

• Class Sarcopterygii – fleshy-finned fish

flying fishgrouper

seahorse

coelacanth

lungfish

Fish Scales

Types of Fish Scales

Fish Scales Allow Age Determination

Teleost Anatomy

General Body Form

Fish Tales?

Primitive Bony Fish – Subclass Chondrostei

• Nonteleost bony fish– Heterocercal tail– Ganoid scales– Lungs

Gar

Subclass Neopterygia –

• Teleost– Swim bladder– Two dorsal fins– Homocercal tail

Bass

Tuna

Walleye

Salmon

Class Sarcopterygii – Lungfish & Coelocanth

Buoyancy

Respiration

Osmotic Regulation

Weird Fish Structures

Life Cycle of Salmonids