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Turtles and Tortoises

Herpetoculture

Pensacola Jr College

Class Reptilia

w    Dry, horny scales

w    Shed outer layer of skin periodically (except some terrestrial turtles)

w    Middle ear, stapes, may have outer ear opening

w    Single occipital condyle

w    Teeth grow continuously (if present)

Class Reptilia (cont’d)

w    Usually 3 chambered heart (except crocodylians)

w    Internal fertilization

    Copulatory organ in males, except in tuatara (cloacal kiss)

w    Amnion surrounds embryo

w    Soft-shelled leathery eggs (or ovoviviparous/viviparous)

Reptile Heart

Reptile Brain

Turtles & Tortoises -- Classification

w    Phylum Chordata

w        Subphylum Vertebrata

w            Superclass Tetrapoda

w                Class Reptilia

w                    Order Chelonia

Order Chelonia

w    Physical characteristics:

    Shell: Carapace = upper, Plastron = lower

    Bony bridge joins plastron to carapace (some hinged for kinesis)

    Scutes (large epidermal scales) cover outer surface

    Ribs/vertebrae fused to inner carapace surface

Carapace

Plastron

Turtle Shells

Order Chelonia (cont’d)

w    Physical characteristics:

    Breathing due to pressure changes in lungs caused by limb movements

    Some respiration through skin, buccal cavity, cloacal bursae

    No teeth

    Horny beak (continuous growth)

Order Chelonia (cont’d)

w    Physical characteristics:

    Yearly growth cycles show as yearly depressions in scutes

    Under 1 pound – 1500 pounds

w    Aquatic, semi-aquatic, or terrestrial

w    Carnivorous, omnivorous, or herbivorous

Order Chelonia (cont’d)

w    All lay eggs on land in nests

w    Internal fertilization

w    Single penis in male

w    No parental care

w    Often loosely social

Turtle male structures

Turtle Skeleton

Turtle Muscular System

Turtle Digestive System

Turtle Respiratory System

Turtle Reproductive Systems

Classification

w    Class Reptilia

w        Order Chelonia

    Family Chelidae

    Family Chelydridae

    Family Cheloniidae

    Family Emydidae

    Family Trionychidae

    Family Testudinidae

Family Chelidae =
side-necked turtles (including matamata),
37 species

Family Chelidae

w    Range: S America, Australia, New Guinea

w    Characteristics:

    Retracts head under lip of shell by bending neck to the side

    Intergular (extra) scute on plastron

w    Aquatic or semiaquatic

Family Chelidae (cont’d)

w    Feeding: carnivorous or omnivorous

w    Egg # = 1 – 25

w    Egg structure = usually inflexible and brittle

w    Egg shape = varies

Matamata (head)

Matamata

Twist-neck turtle

Hilaire's side-necked turtle

Maximilian's snake-necked turtle

Pantanal big-headed turtle

Family Chelydridae = snapping turtles,
2 species

Family Chelydridae

w    Range: N and C America

w    Characteristics:

    Retracts head into shell by bending neck into vertical S-shaped curve (hidden-necked)

    Large head with thick hooked beak and jaw

    Weak plastron with ligament connection to carapace

Family Chelydridae (cont’d)

w    Characteristics:

    Only group that can fully retract head with jaws wide open

    Long tail

w    Freshwater aquatic

w    Feeding: plants, anything that moves, carrion

Family Chelydridae (cont’d)

w    Egg # = 20 – 40

w    Egg structure = flexible

w    Egg shape = spherical

Common snapping turtle

Allligator Snapping Turtle

Family Cheloniidae = sea turtles (Ridley, Green, Hawksbill, Loggerhead),
6 species

Family Cheloniidae

w    Range: tropical to temperate oceans worldwide

w    Characteristics:

    Cannot retract head into shell

    Streamlined low shell with scutes

    Flipper-shaped limbs

    Up to 1000 pounds

Family Cheloniidae (cont’d)

w    Saltwater aquatic

w    Feeding: carnivorous (fish, jellyfish, sponges, crustaceans, etc) except herbivorous Green turtle adults (kelp feeders)

w    Mass female migrations to nest areas every 1-3 years

Family Cheloniidae (cont’d)

w    Egg # = 80 – 200 per clutch (up to 11 clutches in Greens)

w    Egg structure = flexible

w    Egg shape = spherical

Hawksbill

Green Sea Turtle

Loggerhead

Olive Ridley

Different family -- Leatherback

Family Emydidae =
pond and river turtles (terrapins, map, wood, box turtles, sliders, etc), 85 species (largest group)

Family Emydidae

w    Range: most Genera in N America only, but some emydids on each continent except Australia

w    Characteristics:

    Hidden-necked turtles

    Feet usually have webbing between toes and claws

Family Emydidae (cont’d)

w    Freshwater aquatic, semi-aquatic, or terrestrial

w    Feeding: omnivores (varied diet)

w    Egg # = 1-30

w    Egg structure = flexible (temperate) or brittle (tropics)

w    Egg shape = elongated

Pacific pond turtle

American red-bellied turtle

Florida red-bellied turtle

Black wood turtles

Wood turtle hatching

Common box turtle

Eastern box turtle

Common map turtle

Common musk turtle

Eastern painted turtle

Florida Cooter

Red-eared slider

Spotted turtle hatchling

Northern diamond-backed terrapin

Family Trionychidae = softshell  and flapshell turtles,
22 species

Family Trionychidae

w    Range: N America, Africa, Asia

w    Characteristics:

    Hidden-necked turtles

    Elongated neck and snout

    Flat shell with leathery covering instead of scutes

    Reduced plastron

Family Trionychidae (cont’d)

w    Characteristics:

    Ligaments instead of bridge

    Highly webbed feet à paddles

    3 claws per foot

w    Freshwater aquatic

w    Feeding: usually carnivores (fish, crustaceans, insects)

Family Trionychidae (cont’d)

w    Egg # = 4 – 100

w    Egg structure = brittle

w    Egg shape = spherical

Florida softshell

Spiny softshell

Eastern Spiny Softshell

Nile softshell

Chinese softshell

Indian flapshelled turtle

Family Testudinidae = tortoises,
41 species

Family Testudinidae

w    Range: usually tropics & subtropics of each continent except Australia (many on islands)

w    Characteristics:

    Largest non-oceanic turtles (up to 600 pounds)

    Hidden-necked turtles

Family Testudinidae (cont’d)

w    Characteristics:

    Thick domed shells

    Very distinct scutes

    Thick legs and feet

    Stubby unwebbed toes

w    Terrestrial

w    Feeding: generally herbivorous

Family Testudinidae (cont’d)

w    Egg # = 1 – 50

w    Egg structure = varies

w    Egg shape = varies

Aldabra Tortoise

Galapagos tortoises

Galapagos tortoise

African Spurred Tortoises

Desert tortoise

Gopher tortoise

Leopard tortoise

Saddlebacked giant tortoise

Indian star tortoise

Tortoise eggs hatching