Module 12: Amphibian And Reptile Osteology

Question 1

Amphibia subclass

Answer 1

Lissamphibia-all living specimens

Question 2

Caudata (Urodela)

Answer 2

Salamanders
-4 limbs =, tail

Cryptobranchidae - hellbenders “hidden gill”
Ambystomatidae - mole salamanders
Amphiumidae - congo eels
Plethodontidae - lungless salamanders
Necturidae (Proteidae) - mudpuppies
Salamandridae - newts
Sirenidae - sirens

Question 3

Anura (Salientia)

Answer 3

Frogs and toads
-4 limbs, not =

Ascaphidae - tailed frog
Pelobatidae - spadefoot toads
Leptodactylidae - narrow-toed toads
Bufonidae - true toads
Hylidae - tree frogs
Ranidae - true frogs
Myrohylidae - narrow-mouthed toads

Question 4

Apoda (Gymnophiona)

Answer 4

Caecilians
-no legs, worm-like

Question 5

Testudinata (Chelonia)

Answer 5

Turtles

Chelydridae - snapping turtles
Emydidae - freshwater and box turtles
Kinosternidae - mud and musk turtles
Trionychidae - softshell turtles

Question 6

Rhynchocephalia

Answer 6

Tuataras

Question 7

Orders and families

Answer 7

•Order Squamata - snakes and lizards -Suborder Lacertilia-lizards
•Iguanidae - iguanids
•Anguidae - glass lizards
•Teiidae - whiptail lizards
•Gekkonidae - geckos
•Scincidae - skinks
-Suborder Serpentes-snakes
•Boidae - boas and pythons
•Leptotyphlopidae - blind snakes
•Elaphidae - cobras, mambas, coral snakes highly venomous •Viperidae - pit vipers
•Colubridae - nonvenomous constrictors and rear fanged poisonous snakes

Order Crocodilia
Crocodylinae - tropical crocodiles: distinguished by relatively pointed snout
Alligatorinae - alligators and caimens: snout more blunt Gavialinae - gavial or gharial: snout beak-like

Question 8

Skull bones

Answer 8

Amphibians-open, flat, paired occipital condyles
Reptiles-more complete skull, single occipital condyle

Question 9

Vertebrae

Answer 9

Procoelous-concave on cranial surface, convex on caudal surface
-some turtles heterocoelous (saddle-shaped to allow retraction of the neck and restrict twisting)

Question 10

Defining features

Answer 10

Pectoral and pelvis girdle form
Vertebral form
Tooth arrangements
-turtles are Pleurodira (side necks) and Crytodira (hidden necks)—variations in cervical vertebae and shell/scute bones
-frogs and toad-arrangement of teeth

Question 11

Skeletal elements

Answer 11

More rounded
Cartilaginous joint surfaces on long bones, so ends are rounded

Question 12

Reptile post-cranial

Answer 12

Similar to mammals
Have coracoid like birds
Thoracic vertebra and ribs of turtles fuse to carapace

Question 13

Turtle shell

Answer 13

Upper portion-carapace
Lower portion-plastron
Bony plates covered by scutes (what you actually see)
Size shape and arrangement varies with species
Buttressing found on pleural plates closest to notches and plastron at notches or ends of bridge

Question 14

Turtle

Answer 14

Carapace mistaken for human cranium, but diff sutures (more serrated with stippled bits and more convoluted articulation surface)
Lacks meningeal grooves on internal cranium
Human infant or immature bones mistaken for turtle, reptile or amphibian, but reptile/amphibian have complete epiphysis w smooth ends while infant bones are undulating/rough with growth at metaphysis

Question 15

Reptile vs mammal

Answer 15

Thick cortical bone in reptiles, amphibians similar to mammals
Amphibian bones light, reptile heavy

Question 16

Alligator

Answer 16

Transverse processes distinctive in alligator, noticeable step in process for rib articulations