AMNIOTES

1
AMNIOTES

• Probably Also Evolved From Lepidospondyl or
  Temnospondyl
• Separation from Lissamphibian probably 340 MYA
• Includes Following Groups
• Reptiles
• Birds
• Mammals
• Monophyly Supported By
• Extraembryonic Membranes
• Skeletal Characters
• Single Penis

2
Most Temnospondys
Lissamphibia
Amniotes
3
What is a Reptile
Iguanas, Geckos,Snakes
Skinks, Glass Lizards
Birds and Dinos and Crocs
Tuatara
Turtles and Anapsids
Modern Mammals and Kin
Amphibian incl Rep Ancestors
4
What is a Reptile
Iguanas, Geckos,Snakes
Skinks, Glass Lizards
Birds and Dinos and Crocs
Tuatara
Turtles and Anapsids
Modern Mammals and Kin
Modern Amphibians
5
Origin and Relationships of Modern Reptiles
Modern Reptiles Birds/Crocs (By Craggy)
Mammals)
Modern Amphibians
Lungfish
Coelocanths
Ray-finned Fish
6
(No Transcript)
7
MODERN REPTILES
1. Paraphyletic if birds are excluded 2.
United by ecology (and sympleisiomorphies) a.
exothermic b. amniotic eggs c. left overs of
Mesozoic 3. Three major groups a.
Testudines--Turtles b. CrocodiliansBirds c.
Lepidosaura 1) Rynochoccephalia-- Tuatara 2)
Squamata--Lizards and Snakes 4. About 15,800
species world-wide (includes 8700 birds)
8
TESTUDINES--TURTLES
1. Morphology a. Shell b. Anapsid skull c.
Keratinous beak d. Long-lived e. Former
commercial importance is reduced 1)Turtle
soup 2) Fresh meat on ships 3) Tortoise
shell as a material 2. Cosmopolitan in wet
areas 3. Extensive radiation in Mesozoic 4.
260 species world-wide 5. Relationship to
other reptiles is problematic
9
ChelydridaeSnapping Turtles

• 3 Monotypic Genera
• Asia and North America
• Sit and Weight Predators of Slow Water
• Economically Important Game Animal
• Chelydra serpentina
• Macroclemys temminckii

10
EmyidaeBasking Turtles

• 3 12 Genera, 40 Species
• Mostly N/A (except Trachemys)
• Mostly Freshwater Omnivores
• Some Terrestrial (Terrapene)
• Economically Important Game/Pet Animal
• Chrysomys picta

11
TETUDINIDAE Tortoises

• 11 Genera 40 Species
• Southern US to SA, Southern Eurasia Africa
• Truly Terrestrial
• High Domed Shells
• Gravipodal Legs
• Body Pulls Into Shell
• 2 Gopherus in US are on Endangered Species List

12
TRIONYCHIDAE Softshell Turtles

• 14 Genera 27 Species
• NA, Sub-Saharan Africa, China, Japan, SE Asia
• Highly Aquatic
• Little Ossification of Shells
• Webbed Feet
• Very Long Necks
• Flat Bodies
• 2 Apalone spinifer A. mutica
• Remain an Important Food Item

13
KINOSTERNIDAE Mud Musk Turtles

• 3 Genera 22 Species
• Eastern NA through SA
• Terrestrial Within Water?
• Fairly Small (Local Ones)
• Walk on Bottom
• Hinged Shells Allow Complete Retraction
• Able to Move Between Ephemeral Pools
• Release Musk as a Defense
• Kinosternon Sternothorus

14
CHELONIDAE DERMOCHELYIDAE Sea Turtles

• 5 Genera 6 Species Monotypic
• Temperate and Tropical Water Worldwide
• Large Size 70-250cm
• Leatherbacks are Largest
• Legs modified for swimming
• Come ashore only to lay eggs
• Most severely reduced in numbers
• Fresh Meat Eggs
• Uses of Shells
• Disturbance of Eggs
• Increase in Predation on Beaches
• Floating Trash (Nets and Bags)
• Flagship Species For Beaches

15
CHELIDAE Snake-necked Turtles

• 11 Genera 50 Species
• South America, Australia, New Guinea
• Long-necked Turtles of Slow Water
• Ecological Equivalents of Apalone, Chelydra
• Chelodina rugosa lays eggs underwater

16
Undiscussed Families

• Pelomedusidae
• 2 Genera 18 Species, Africa
• Similar to Kinosternidae
• Podocnemidae
• Flat Shells and Active Swimmers
• 3 Genera 8 Species
• Bataguridae
• 23 Genera, 65 Species
• Mostly Old World, One in Central America
• Ecological Equivalents of Emyidae
• Dermatemydidae--1 Species in S Mexico
• Carettochelyidae-- 1 Species in New Guinea

17
LEPIDOSAURIA
I. Rynchocephalia--Sphenodon--Tuatara 1.
Separated by a. Heterodont dentition b. Teeth
on palentine bone c. Externally resemble
iguanas 2. 2 Species 3. Restricted to New
Zealand 4. Breeding program at Saint Louis Zoo
18
LEPIDOSAURIA

• II. SquamataSnakes, Lizards, Amphisbeanians
• 1. Highly Kinetic Skulls (Parts Move)
• 2. Hemipenes
• Shed Skin All at Once
• Dominant Desert Life Form
• Dominant Fossorial Vertebrate
• Limb Reduction is Common
• Snakes
• Lizards
• Amphisbeanians

19
MOST RECENT PHYLOGENETIC HYPOTHESIS
Skinks
Geckos Amphisbaenia
Snakes
Tuatara
Iguana
20
SCINCIDAE Skinks

• 115 Genera 1260 Species
• Nearly Cosmopolitan
• Dermal Bones--Amour Plate
• Many Are Terrestrial Insectivores
• Some Similar to Snakes
• Most are Robust Limbed
• Mostly Diurnal
• 2 Eumeces (fasciatus and laticeps)
• Adult vs Juvenile Color
• Tail Autonomy

21
IGUANIDAE Iguanas

• 8 Genera 34 Species
• Several Families Broken Out
• Crotophytidae--Collard Lizards
• Phrynosomatidae--Spiny Lizards
• Sceloporus, Uta, Phrynostoma
• Desert NA Lizards
• Polychrotidae
• American Chamelions--Anolis
• The generalized Moderate-sized Lizard

22
GEKKONIDAE Geckos

• 97 Genera 1050 Species
• Gondewanna Land Nearby parts of Asia North
  America
• Most Lizards in the Tropics
• Mostly Arboreal Saxicolous Insectivores
• Unique Toe Pads--Can Climb Glass
• Popular in Pet and Zoo Trades
• Commonly Introduced to NA

23
TEIIDAE Racerunners

• 9 Genera 125 Species
• NS America
• Introduced in Spain
• Active Diurnal Predators
• Many are Parthenogenic
• Asexual Reproduction
• Females Mate with Outside Male
• Genes From Sperm Not Incorporated
• Speciation by Hybridization
• Cnemidophorus

24
ANGUIDAE Glass Lizards

• 13 Genera 110 Species
• NA, SA, Eurasia, Africa
• Readily Autotomize Tail
• Limb Reduction is Common
• Widespread, but Rare in NA
• Ophisaurus

25
HELODERMATIDAE Venomous Lizards

• 1 Genus 2 Species
• SW USA to Guatemala
• Venomous Saliva
• Must Chew to Envenomate
• Mexican Beaded Lizard
• Gila Monster
• Popular in Pet and Zoo Trades
• Both Endangered by Over collection
• Eat Mostly Vertebrates

26
CHAMAELEONIDAE Chameleons

• 6 Genera 130 Species
• Mostly Madagascar, Africa, Mideast, India, Sri
  Lanka
• Introduced in Spain
• Mostly Arboreal Insectivores
• Pincher-like Hands (Zygodactylus--fused fingers)
• Long Tails
• Independent Moving Eyes
• Long, Long Tongues
• Some Ground-dwelling Forms (Pigmy)
• Popular in Pet and Zoo Trades

27
Undiscussed Families

• Agamidae
• 45 Genera 380 Species, Africa, S Asia,
  Australia
• Dibamidae--Small Burrowing Lizards, Reduced Limbs
• 2 Genera 10 Species
• Gynophthalmidae
• 35 Genera, 150 Species, South America
• Lacertidae--1 Species in S Mexico
• 25 Genera 250 Species, Mostly African
• Xantusiidae-- 3 Genera 18 Species, Central
  America
• Cordylidae--4 Genera, 40 Species--Africa
• Xenosauridae--1 Genus, 6 Species
• Shinisauridae--Monotypic
• Varanidae--1 Genus, 40 Species
• Lanthanotidae--Monotypic

28
AMPHISBAENIA

• Amphisbaenidae--
• 19 Genera 135 Species
• West Indies, SA, Sub-Saharan Africa
• Rhineuridae--Rhineura floridana
• Trogonophidae
• 4 Genera 6 Species
• North Africa and Middle East
• Bipedidae
• 1 Genus 3 Species, Baja California
• Unusual Snake-Like Lizards
• All but Bipes are legless
• Elongate
• Multiple Annulations
• Right Lung Reduced
• Skin Moves Independent of Trunk
• Tails Do Not Regenerate

29
Remember Snakes Are Just Lizards

• No Legs (almost)
• Long Vertebral Columns (120 Before Tail)
• No Eye Lids
• Focus By Moving Lens In and Out
• Reduced Left. Lung
• No External Ears
• Continued Skull Reduction
• Probably Evolved From Burrower
• Heat Sensing Pits Common
• 2500 Species

30
COLUBRIDAE Normal Snakes

• 320 Genera 1800 Species
• Cosmopolitan
• Trashcan Taxon
• Many Other Families Are Being Split Off
• Most Common Snakes
• Sensu strictu
• 150 Genera, 700 Species
• Cosmopolitan
• Coluber
• Masticophis
• Tantilla
• Elaphe
• Lampropeltis
• Opheodrys
• Pituphis
• Still a Trashcan

31
NATRICIDAE Water Snakes

• 40 Genera 210 Species
• Holoarctic, Africa, Australia, India
• Mostly Aquatic or Semiaquatic
• Natrix
• Nerodia
• Thamnophis
• Storeria
• Regina
• Virginia
• NA Versions are Temperamental Viviparous
• Many Actually Do Well With Settlement
• Some Eurasian Forms Are Truly Terrestrial

32
XENODONTIDAE Rear-Fanged Snakes

• 65 Genera 350 Species
• Mostly South America
• North American Forms Are a Problem
• Diadophis
• Ring-necked Snakes
• Extirpated in Indianapolis
• Masticophis
• Worm Snakes
• Heterodon
• Specialized Toad Eaters
• Upturned Snout Scale
• Rear Fanged
• Defense Displays

33
LEPTOTYPHLOPIDAE Blind Snakes

• 2 Genera 90 Species
• Africa, Mideast, SA, SW USA
• Small Burrowing Snakes
• Some Populations in Barn Owl Nests
• Mostly Myrmecophagus
• Leptotyphlops dulcis and humilis Have Broad Diets

34
VIPERIDAE Vipers

• 20-27 Genera 228 Species
• NSA, Africa, Eurasia
• US Species are in Crotalinae (Pit Vipers)
• Mostly Ambush Predators
• Rattlesnakes
• Cottonmouths
• Copperheads
• Old-World Vipers
• Most Bites Are to Academics Amateurs
• Venom is Mostly Hemolytic and Cytolytic
• Causes Massive Tissue Damage
• Most NA Species Are Not Fatal

35
ELAPIDAE Cobra and Kin

• 62 Genera 300 Species
• Most of World Except Upper Temperate Zones
• Mostly Active Predators
• Cobras
• Coral Snakes
• Sea Snakes
• Most Australian Snakes
• Brown Snake a Major Pest
• Venoms Tend to be Neurotoxic
• Frequently Available in Pet Trades

36
BOIDAE Boas, Pythons, and Kin

• 20 Genera 74 Species
• All Tropical and Subtropical Regions
• Formerly in Several Families
• Wide Variety of Sizes
• Eunectes murimus 9m
• Python reticulus 9m
• Tree Boas lt 1m
• Many are Arboreal
• Many Ground-Based Predators
• Popular in Pet and Zoo Trades
• Leads to Frequent Introductions

37
Undiscussed Families

• Anomalepididae
• 4 Genera 15 Species, SA small insectivorous
  species
• Typhlopidae
• 6 Genera 200 Species, Gondwanal, Similar to
  Above
• Anomochilidae 1 Genus, 2 Species--Malaysia
• Aniliidae 1 Species in Amazonia
• Uropeltidae Genera 55 Species India SE Asia
• Xenopeltidae2 Species, India
• Loxocemidae 1 Species Central America
• Xenophidiidae 1 Genus, 2 Species Malaysia
• Tropidophiidae 2 Genera, 31 Species Central
  SA
• Bolyeridae--1 Genus, 2 Species 1 Island in
  Indiana Ocean
• Arcochordidae--h1 Genus 3 Species Australasia
• Aractaspididae 1 Genus 18 Species Africa and
  Mideast

38
Crocodilians
1. Morphology a. 2 return to sprawling
form b. Large Elongate c. Specialized for
Aquatic Life d. Despite rarity remain
commercially important 2. Primarily Tropical
and Subtropical 3. Extensive care of young 4.
Very extensive radiation in Triassic a.
Dinosaur Origins/Competition b. Only surviving
Archosaurs c. Many Lifestyles 5. 22 species
world-wide
39
ALLIGATORIDAE Alligators

• 3 Genera 8 Species
• NA and China
• Lower Teeth are Not Visible
• Alligator mississippiensis
• Common in SE US
• Once Endangered
• Now a Pest
• Important Leather Source
• Important Meat Source
• Caimans--Common Pets
• Dumped Pets Show Up Everywhere

40
CROCODYLIDAE Chameleons

• 2 Genera 13 Species
• Caribbean, Central SA, Africa, India, Asia,
  Australia
• Reputation for Man-Eating
• Deserved by Nile and Saltwater Crocs

41
GAVIALIDAE Gharrials

• 2 Monotypic Genera
• India to New Guinea
• Ichthyfagous
• Feeding Style

42
MOST RECENT PHYLOGENETIC HYPOTHESIS
Crocodylidae
Gavialidae
Alligatoridae
Morphology Suggests A Close Relationship Between
Crocs and Gators? How is This possible?