FNR 24150 Herps Exam I

Reptile Characteristics

Reptile Characteristics

Increased brain size
Skeletal structure improved
More effective jaw
Amniotic eggs
Scales

Order Testudines

Turtles

Family Cheloniidae

hard-shelled Sea Turtles

Family Dermochelyidae

Leatherback
endotherm

Family Chelydridae

Snapping Turtles
long tails
sit and wait predation strategy
alligator + common (found in indiana)
Ability to respire through throat (Pharyngeal respiration)

Family Kinosternidae

Mud & Musk Turtles
eat aquatic invertebrates
large jaws
forage/mate on water
hibernate on land

Family Emydidae

Basking, Marsh & Box Turtles

Emydidae (Basking, Marsh & Box Turtles)

Sexual Maturity at 20 years
Sex determined by temperature
basking on logs/rocks
males smaller than females (sexual dimorphism)

Family Testudinidae

Tortoises

Testudinidae (Tortoises)

50 species
Terrestrial
Maturity at 20 years

Family Trionychidae

Soft-shelled Turtles

Trionychidae (Soft-shelled Turtles)

26 species
Genetic sex determination (only turtle)
Fully aquatic
Ability to respire through throat (Pharyngeal respiration)

Squamata

1900 species
Diversity of reptiles lays in squamata
Lizards can blink & geckos cannot
Lizards have ears
Internal fertilization

Family Gekkonidae

Geckos

Gekkonidae (Geckos)

970 species
Vili on feet

Vili

Suction cups on feet

Family Iguanidae

Iguanas & anoles

Iguanidae (Iguanas & anoles)

Used to be huge family now only 34 species
"New World" Iguanas
Oviparous

Family Phrynosomatidae

Spiny Lizards

Phrynosomatidae (Spiny Lizards)

125 species
Broad diversity
Oviparous
"New World" Family
Interesting defense behaviors

Agamidae

400 species
"Old World" Iguanas
Prominent spines
All but one species is Oviparous

Polychrotidae (anoles & friends)

650 species
Arboreal lifestyle
Oviparous
Nicely colored dewlap
Mating is color specific between species & push up based

Family Anguidae

Glass or Alligator Lizards (Legless Lizards)

Anguidae (Legless Lizards)

120 species
Snake-like
Osteoderms
2/3 of body is tail
Fossorial
Can drop tail

Family Helodermatidae

Beaded Lizards

Helodermatidae (Beaded Lizards)

2 species
Bead-like scales
Osteoderms
Aposematic Coloration
Only two venomous lizards
Have to chew for venom to get in wound
Semi-arboreal
Oviparous
10 months for eggs to catch

Family Teiidae

Whiptails & Racerunners

Teiidae (Whiptails & Racerunners)

110 species
"New World"
Very small dorsal scales & large ventral scales
Diurnal
Most are oviparous
Some are parthenogenic

Family Scincidae

Skinks

Scincidae (Skinks)

1200 species
Osteoderms
Can drop tail
All reproductive strategies

Serpents (Snakes)

Bifurcated tongue
Jacobson organ
Most species only have 1 lung
All reproductive strategies
4 venomous snakes in IN

Family Boidae

Boas

Boidae (Boas)

63 species
Primitive species
Vestigial pelvic girdle
Legs than no legs
Heat seeking pits on sides of mouth
Most are Ovoviparous

Family Viperidae

Vipers

Viperidae (Vipers)

Venomous
Hinged fangs that are hypodermic (Hallow)
Loreal pit (Heat seeking organ) One on each side of face
Hemotoxican (Digest tissue)
Mostly Viviparous
Bite and Follow

Family Elapidae

Cobras & Corals

Elapiade (Cobras & Corals)

280 species
Neurotoxic venom
Oviparous
Bite and hold a little longer than Vipers

Family Colubridae

Snakes

Colubridae (Snakes)

Used to be 2,000 species, now just 650 species
Ovoviparous & Viviparous

Family Natricidae

Water Snakes

Natricidae (Water Snakes)

200 species
All aquatic or have aquatic life stage

Family Dipsadidae

Snakes

Dipsadidae (Snakes)

700 species
Hide
Oviparous

Reptile Taxonomy

Increased brain size
More effective jaw
Scales
Amniotic eggs
Well developed lungs
Skeletal structure improved

Amniota

Permian

Synapsids, Diapsids & Anapsids

Permian

Anapsids

1st reptiles
No temporal fenestrae (No holes..tehe "holes")

Synapsids

Single hole (mammals & mammal-like reptiles)

Diapsids

Two holes (Crocs, snakes, lizards & maybe turtles)

Mesozoic (Reptiles)

Dominated by reptiles
(Dinosaurs)
Radiation of Reptiles
250 mya

Archosauromorphs

"Ruling reptiles" of Mesozoic
1st major diapsid lineage
ancestral to crocodilians, birds, turtles

Casineria

Early Carboniferous
340 mya
Salamander-like
1st amniote
Transitional form from amphibians to reptiles

Hylanomus

1st Lizards
Carboniferous
315 mya
Anaspid
sharp teeth
Perhaps earliest known reptile

Crocodylians

Surviving archosuars
temperature dependent sex determination (cooler temps is female)

Sarcosuchus

Super croc
"Flesh crocodyle"

Lepidosauromorphs

Appeared late Permian
2nd Major Diapsid lineage
Ancestral to squamates (Snakes, Lizards & Tuatuara)

Tuatuara, Sphenodontia

Living Fossils from Triassic
Endemic to New Zealand
200 myo

Odontoochelys

Late Triassic
220 mya
"toothed shell"
Turtle

Proganochelys

Late Triassic
210 mya
"early turtle"
Has few teeth

Eileanchelys

Late Jurrasic
165-160 mya
Earliest pond turtle

Archelon

Late Cretaceous
75-65 mya
"Ruling turtle"
12 ft. ~2 tons
Leathery Shell
largest ever turtle

Archosaurians

Mammals, Birds & Crocs

What is the limiting factor of Reptiles & Amphibians?

Temperature

Heat Exchange in Ectotherms

Radiation
Convection
Conduction

Ectotherms produce low metabolic heat?

Yes

Major drivers in Ectothermy

Rate of water loss
Heat Exchange
Surface:Volume Ratio (smaller animals gain/lose heat or lose water faster)

Amphibians have a lower metabolic rate than reptiles?

True

Conduction

Heat exchange with a surface

Reptiles tend to have higher body temps than anything else?

True

Salamanders have lowest body temperature and lizards have highest?

True

ATR (Activity Temperature Range)

27-35 degrees C
optimal temperature range

How many chambers do amphibians have?

Two atria
One ventricle

How efficient is the amphibian circulatory system?

Not highly efficient

Amphibian lymphatic system open system or both?

Open System

Who has lymph hearts?

Amphibians

Amphibian blood

Nucleated

Reptile Heart

No single "model"
Typically three chambers

Amphibian Respiratory System

Air moves in and out by a buccopharyngeal force pump mechanism

Are amphibian positive or negative pressure breathers?

Positive Pressure Breathers

Reptilian Lungs

Simple sac-like lungs
Sacs called faveoli
Snakes have single lung

Vitellogensis

Accumulation of nutrients in the cytoplasm of the developing egg

Salamanders have what kind of fertilization?

Polyspermic

Sperm storage organ in Salamanders?

Spermatheca

Gynogenesis

Male is only needed to activate the zygote

Two growth Pulses

Embryonic
Juvenile

All Reptiles have what three Reproductive things in common?

Internal Fertilization
Direct Development
Amniotic Eggs

In reptiles, vitellogenin is selectively absorbed by oocytes and enzymatically converted to yolk proteins, what is this process called?

Pintocytosis

Cleidoic Egg

Shelled

Membranes in Cleidoic egg

Allantois
Chorions
Amnions

Turtles and Crocs Penises

Spongy connective tissue erects via vascular pressure

Parthenogenesis

Females reproduce without the involvement of males or sperm
(Clonal)

Teiidae have what reproductive strategy?

Parthenogenesis

Parental Care Types

Pre-depositional: Egg size and quality
Post-depositional: Nest location
Live-bearing: Complete control over everything

megachirella

oldest lepidosaur fossil
lived during triassic 240 mya

plasteron

on belly of turtles, defends against predators

dormancy types

hibernation
freeze tolerance
aestivation

hibernation

body temp allowed to track operative temp
metabolic activities slowed

freeze tolerance

cryoprotectants prevent cells freezing
found in early spring breeders

aestivation

in dry desert environments
animals retreat to burrows with high humidity into dormancy