Turtles

Turtles are a group of reptiles at their evolutionary zenith
Currently there are 13 different families represented by approximately 300 species
Turtles are found in every region of the world except for the extreme Polar regions
There are 29 species and 7 different families of turtles living in Texas

Turtles are the only vertebrate with a shell
The ribs are fused into the inside of the shell
Turtles have a urinary bladder
Turtles do not possess teeth. Instead they utilize a sharp cusp to cut off pieces of food
Turtles have well developed hearing and eyesight

Male turtles and crocodilians are the only reptiles with a penis for a copulatory organ
Females lay eggs. eggs The number of eggs produced produced depends upon the age size and species
of turtle laying the eggs. Clutch size may vary from 2‐100+
Males often locate females by sight and then confirm their sex by smell and behavioral
cues
T tl l t h t it d t
Turtles are slow to reach maturity and must
produce several offspring each year in order to
maintain the survival of the species

Females often nest under the cover of darkness and they may dig a number of holes
before finally laying their eggs.
The sex of most turtles is dependent upon their temperature during incubation
Upon hatching the young turtle uses an egg tooth (caruncle) to cut open the egg shell.
Hatching usually occurs during the late summer and depending upon the hardness of
the ground, hatchlings may remain buried until the arrival of spring rains

With the exception of most tortoises, turtles are largely omnivores and opportunistic
consumers of a variety of food items.
Most freshwater species (except for the soft shell turtles and the mud and musk turtles)
will consume vegetative matter including aquatic plants, fallen fruits and algae
Some have adapted interesting feeding strategies to secure fish
Most freshwater species are simply not fast enough to capture healthy fish
The perception of turtles being a pest or nuisance are most often false. The idea of
nuisance turtles is often promoted by businesses dealing with the sale of native turtles
to Asian food markets.
Many of the fish captured by turtles are old or unhealthy. The removal of these fish
essentially increases the health of the fish population

Like all reptiles, turtles are cold blooded and their internal body temperature is dictated
by the temperature of their environment.
Most aquatic species devote considerable amounts of time to basking in the sun
This not only increases the body’s metabolic function by raising the body temperature, it
also helps rid the body of external parasites and excess algae

Texas turtles are often active throughout the year except for exceptionally cold winters
and hot and dry summers
Turtles often wander about in search of ideal
nesting sites and better locations to live. The
peak k level l lof f activity i i occurs ffrom spring i to
autumn

Fossil record dates back to the Triassic some 245 million years ago
Texas turtles have a well documented fossil record with some of the most remarkable specimens found in Cretaceous
Texas turtles have a well documented fossil record with some of the most remarkable specimens found in Cretaceous
deposits

•
The sea turtles Family Cheloniidae
• Sea turtles of the family Cheloniidae represent a wide spread group of turtles that occur in virtually all of the
worldʹs temperate and tropical seas. Throughout the world, five genera and six species are known to exist. In
Texas, four different species have been found in the Gulf coast and on its shores. These large turtles have a
carapace covered in keratinized scutes and depending upon the species can range in size from 30 inches (100 cm)
to 39 inches (124 cm) and weight as much as 95 pounds (43 kilograms to 400 pounds (200 kg).
• Sea turtles are highly specialized for an aquatic life in a marine environment. The most noticeable difference
between sea turtles and most other turtles are the fore and hind limbs which have been modified into
flippers. The physiology of these reptiles is also of interest as sea turtles must effectively regulate the amount of
salt taken into their bodies. Salt secretion glands located near the corner of the eye help rid the body of excess
salts.
• Males rarely, if ever leave the water. Coming ashore is mostly a task reserved for the females as they continue the
millennia old ritual of females returning to the same nesting beaches that they hatched from
themselves. Depending upon the species, females can lay 50‐160 leathery round eggs. Females come to shore
under the cover of darkness to lay their eggs
• Sea turtles are facing eminent extinction due to man made pressures ranging from pollution, incidental deaths
from the fishing industries and the direct take of eggs and slaughter of adults for food.
• The Sea Turtles: Family Cheloniidae
• The Loggerhead sea turtle (Caretta caretta)
• The Green sea turtle (Chelodina mydas)
• Hawksbill sea turtle (Eretmochelys imbricata)
• Atlantic Ridley (Lepidochelys kempii)

Green sea turtle (Chelonia ( mydas) y )

Kemp’s p Atlantic Ridley y (Lepidochelys ( p y kempii) p )

•
•
Family Chelydridae The Snapping Turtles
Chelydrid turtles are undeniably easy to recognize. The family Chelydridae is represented by two species, the
common snapping turtle (Chelydra serpentina) and the alligator snapping turtle (Macrochelys temminckii).
• Today members of the family Chelydridae are found in the Western Hemisphere, and primarily in the Northern
Hemisphere. However it should come as little surprise that such a prehistoric looking family of turtles has a fairly
well documented fossil history. dating back to the Paleocene with the discovery of Protochelydra zangleri.
• Common snapping turtle (Chelydra serpentina)
• Alligator snapping turtle (Macrochelys temminckii)
• Snapping turtles can be found in various habitats. These photos were both taken in Anderson County, Texas. One
ddepicts i t a swamp ( (above b lft) left) and d th the other th ddepicts i t a seasonally ll flooded fl d d forest. f t Whil While th the swamp provides id a more
permanent habitat for these turtles heavy rains can cause the water levels in creeks, rivers and lakes to rise often
flooding adjacent areas. This is one manner by which these turtles relocate to different habitats. Both the common
and alligator snapping turtle have been found in Anderson County, Texas.

Family Dermochelyidae Dermochelys coriacea The leatherback sea turtle

Family y Emydidae: y Box turtles, Cooters, Painted turtles, Sliders and Terrapins p

• Family Emydidae: Box turtles, Cooters, Painted turtles, Sliders and Terrapins
• Members of the family Emydidae are probably the most commonly encountered family of turtle in Texas. Seen crossing roadway
wandering in fields, basking on logs or swimming in various bodies of water emydid turtles represent the greatest diversity of tur
in Texas.. Within Texas representation of this family is comprised of 7 genera and 14 species.
• Western painted turtle (Chrysemys picta belli)
• Southern painted turtle (Chrysemys picta dorsalis)
• Western Chicken turtle (Deirochelys reticularia miaria)
• Cagleʹs map turtle (Graptemys cageli)
• Sabine map turtle (Graptemys ouachitensis sabinensis)
• Mississippi map turtle (Graptemys pseudogeographica kohnii)
•
Texas map turtle (Graptemys versa)
•
Texas diamondback terrapin (Malaclemys terrapin littoralis)
• River cooter (Pseudemys concinna)
• Rio Grande river cooter (Pseudemys gorzugi)
• Texas river cooter (Pseudemys texana)
• Big Bend slider (Trachemys gaigeae)
• Red eared slider (Trachemys scripta elegans)
• Three toed Box turtle (Terrapene carolina triunguis)
• Ornate Box turtle (Terrapene ornata)
• Desert Box turtle (Terrapene ornata luteola)

The Western Chicken Turtle (Deirochelys reticularia miaria)

Cagleʹs map turtle (Graptemys cageli)

Mississippi map turtle (Graptemys pseudogeographica kohnii)

River cooter (Pseudemys concinna)

Rio Grande river cooter (Pseudemys gorzugi)

Ornate box turtle (Terrapene ornata)

Big Bend slider (Trachemys gaigeae)

Red eared slider (Trachemys ( y scripta p elegans) g )

• Family Kinosternidae: Mud and Musk turtles
• The family y Kinosternidae consists of two genera g and twenty y three species. p Four species p belong g to the genus g
Sternotherus (musk turtles), and nineteen belong to the genus Kinosternon (mud turtles). The family Kinosternidae
is distributed from southeastern Canada to the United States east of the Rockies and southward to Brazil. These
are small turtles, with the largest species in Texas achieving a maximum length close to 7 inches (** cm).
• Members of this family are aquatic and sometimes seen patrolling the bottoms of brackish marshes, creeks,
flooded fields, lakes, ponds, and rivers. Mud and musk turtles engage in moderate amounts of basking. However,
because the turtles turtles’ lifestyle causes significant algae growth on their shells shells, observers occasionally mistake an
algae‐covered turtle for a rock. Kinosternid turtles are capable of remaining submerged underwater without
surfacing for several minutes. Their underwater ability is due in a large part to buccopharyngeal respiration.
• Mud and musk turtles have a carapace that is oval‐shaped and has twenty‐three marginal scutes including the
cervical scute. The plastron has ten to eleven scutes and may have a flexible hinge.
• As evidenced by fossil material, the family Kinosternidae has been around for a long time. A fossil of Xenochelys
formosa was discovered in deposits in South Dakota that dated to the Oligocene Epoch (23 million to 38 million
years ago). This specimen is the oldest known representative of the family.
• 2 genera and 5 species of kinosternid turtles are found in Texas.
• Yellow mud turtle ( Kinosternon flavescens)
• Big Bend mud turtle (Kinosternon hirtipes murrayi)
• Mississippi mud turtle ( Kinosternon subrubrum hippocrepis)
• Razorback musk turtle (Sternotherus carinatus)
• Common musk turtle or Stinkpot (Sternotherus odoratus)

Yellow mud turtle (Kinosternon flavescens)

Mississippi mud turtle (Kinosternon subrubrum hippocrepis)

Common Musk turtle or Stinkpot (Sternotherus odoratus)

Texas tortoise (Gopherus berlandieri)

Family Trionychidae: The Soft shelled turtles

Family Trionychidae: The Soft shelled turtles
• With fifteen genera and thirty species species, the family Trionychidae occurs throughout most of the world world. These distinctive
turtles have a range that includes North America, Africa, southern and eastern Asia, and the East Indies to New Guinea.
Fossil records from the late Jurassic Period provide evidence that this family’s distribution once included Europe and
South America.
• One genus and four species comprise the soft-shelled turtle diversity in North America. In general, North American softshelled
turtles are moderately y sized. The Florida soft-shelled turtle (Apalone ( p ferox) ) attains the largest g size at 25 inches ( (63
centimeters). This species has a distribution that includes southern South Carolina, central Georgia, eastern Alabama, and
Florida.
• The smooth soft-shelled turtle (Apalone mutica) is one of two species inhabiting the central United States and reaches
14 inches (35 centimeters) in carapace length. Unlike its cogener, the spiny soft-shelled turtle (A. spinifera), this species
lacks tubercles on the anterior portion of its carapace.
• The spiny soft-shelled turtle has the widest range of all the North American soft-shelled turtles. This species has a
geographic distribution that includes southern Ontario and Quebec, Canada, to northern Florida westward to Montana and
southeastern California. It also occurs south of the Rio Grande in Juarez, Coahuila, Nuevo Leon, and Tamaulipas, Mexico.
• Two species of soft shell turtle occur in Texas.
• The smooth soft shell turtle (Apalone mutica)
• The spiny soft shell turtle (Apalone spinifera)

After more than 200 million years, turtles are currently facing possible depletion and
extinction unlike any other period in known history
Their problems are caused by human activity
Loss of habitat, road way mortality, collection for the pet trade and harvest for the
Asian food markets can seriously deplete and extirpate populations
Thousands of turtles are currently harvested from public and private waters and sold
as “sea food” to China. This activity y has already y depleted p much of southeast Asia’s
turtle populations and now the Chinese are seeking turtles from other countries.
The take of turtles from the wild for a source of food is unsustainable
Our turtles should be a source of interest and pride in the natural history and
heritage of Texas

Don’t buy wild caught turtles. Most pet stores sell wild caught turtles if you decide
to acquire a pet turtle purchase one from captive bred stock or adopt one from an
animal rehab.
Don’t eat Texas turtles. Asides from the aspect of unsustainability, turtles
accumulate and retain more toxins and pollutants pollutants (methyl mercrury mercrury, pcbs pcbs, etc) in
their bodies than fish.
Help the turtle cross the road. Turtles don’t know what cars are and their shells
always burst when hit by a vehicle resulting in a painful and unnecessary death