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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

Kemp’s Ridley

Flatback

Different family -- Leatherback

Family Emydidae =
pond and river turtles (terrapins, map, wood, box turtles, sliders, etc), Together with Eurasian terrapins make up the largest group (>100 sp)

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 ŕ 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

Turtle Conservation Examples

w  Turtle Survival Alliance

w  Western Pond Turtles