Names for Pet Turtles and Tortoises

Names for Pet Turtles and Tortoises

Turtles are diapsids of the order Testudines (or Chelonii) characterized by a special bony or cartilaginous shell developed from their ribs and acting as a protect. "Turtle" may refer in order to the order as the whole (American English) or to fresh-water and sea-dwelling testudines (British English). The order Testudines includes both extant (living) and extinct species. The earliest recognized members of this team date from 220 mil years ago, making turtles one of the earliest reptile groups and the more ancient group than snakes or crocodilians. Associated with the 356 known species alive today, some are usually highly endangered.

Turtles are usually ectotherms—animals commonly called cold-blooded—meaning that their internal temperature varies according to the particular ambient environment. However, due to the fact of their high metabolic rate, leatherback sea turtles have a body heat that is noticeably higher than that of the particular surrounding water. Turtles are usually classified as amniotes, together with other reptiles, wild birds, and mammals. Like other amniotes, turtles breathe air flow and do not place eggs underwater, although several species live in or around water. The study of turtles is known as cheloniology, after the Greek term for turtle. It is usually also sometimes called testudinology, after the Latin name for turtles.

Differences exist in usage of the particular common terms turtle, tortoise, and terrapin, according to the range of English being used. These terms are common names and don't reflect accurate biological or taxonomic distinctions.

Turtle may either recommend to the order because a whole, or to particular turtles that create up a form taxon that is not monophyletic, or may be restricted to only marine species. Tortoise usually pertains to any land-dwelling, non-swimming chelonian. Terrapin can be used in order to describe several species of small, edible, hard-shell turtles, typically those found in brackish waters.

In North America, all chelonians are usually commonly called turtles. Tortoise is used only in reference to fully terrestrial turtles or, more narrowly, just those members of Testudinidae, the family of modern land tortoises. Terrapin may refer to small semi-aquatic turtles that live in new and brackish water, in particular the diamondback terrapin (Malaclemys terrapin). Although the people of the genus Terrapene dwell mostly on land, they are referred to as box turtles rather than tortoises. The particular American Society of Ichthyologists and Herpetologists uses "turtle" to describe all types of the order Testudines, whether or not they are land-dwelling or sea-dwelling, and uses "tortoise" as a more specific term for slow-moving terrestrial types.

In the United Kingdom, the word turtle is utilized for water-dwelling species, including ones known in the particular US as terrapins, but not for terrestrial species, that are known only as tortoises.

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The word chelonian will be well-liked by veterinarians, scientists, and conservationists working with these animals as a catch-all title for any member of the superorder Chelonia, which includes all turtles living and vanished, as well as their particular immediate ancestors. Chelonia is based on the Ancient greek word for turtles, χελώνη chelone; Greek χέλυς chelys "tortoise" is also utilized in the formation of medical names of chelonians. Testudines, on the other hands, is based on the Latin word for tortoise, testudo. Terrapin comes from an Algonquian word with regard to turtle.

Some languages do not have this distinction, as all of these are known by the same name. For example , within Spanish, the word tortuga is used for turtles, tortoises, and terrapins. A sea-dwelling turtle is tortuga marina, a freshwater types tortuga de río, and a tortoise tortuga terrestre.

The largest living chelonian is the leatherback ocean turtle (Dermochelys coriacea), which usually reaches a shell length of 200 cm (6. six ft) and can reach a weight of more than 900 kg (2, 1000 lb). Freshwater turtles are usually generally smaller, but with the largest species, the particular Asian softshell turtle Pelochelys cantorii, a few people have been reported up to 200 cm (6. 6 ft). This dwarfs even the better-known alligator snapping turtle, the largest chelonian in North The united states, which attains a cover length of up to 80 cm (2. six ft) and weighs because much as 113. four kg (250 lb).

Huge tortoises of the genera Geochelone, Meiolania, and others were relatively widely distributed all over the world into prehistoric periods, and they are known to have got existed in North plus South America, Australia, and Africa. They became wiped out at the same period as the appearance of man, and it is usually assumed humans hunted them for food. The only surviving giant tortoises are usually on the Seychelles and Galápagos Islands and can develop to over 130 cm (51 in) in duration, and weigh about three hundred kg (660 lb).

The particular largest ever chelonian has been Archelon ischyros, a Late Cretaceous sea turtle identified to have been up to 4. 6 m (15 ft) long.

Box turtle Wikipedia

The smallest turtle is the speckled padloper tortoise of South Africa. It measures no more than 8 cm (3. 1 in) long and weighs about 140 g (4. 9 oz). Two other species of small turtles are the American mud turtles and musk turtles that live in an area that ranges from Canada to South America. The cover duration of many species within this group is less than 13 cm (5. 1 in) long.

Turtles are divided into two groups, according to how they retract their necks into their shells (something the ancestral Proganochelys could not do). The mechanism of neck retraction differs phylogenetically: the particular suborder Pleurodira retracts laterally aside, anterior to glenohumeral joint girdles, while the suborder Cryptodira retracts straight back again, between shoulder girdles. These types of motions are largely due to the morphology plus arrangement of cervical vertebrae. Of all recent turtles, the cervical column consists of nine joints and eight vertebrae, which are usually individually independent. Since these vertebrae are not joined and are rounded, the particular neck is more versatile, being able to bend in the backwards and sideways directions. The primary function and evolutionary implication of neck retraction is usually thought to be regarding feeding rather than protection. Neck retraction and testing extension allows the turtle to reach out further to capture prey while swimming. Neck expansion creates suction once the head is drive forward and the oropharynx is expanded, and this morphology suggests the retraction function is for serving purposes as the suction helps catch prey. The protection the shell provides the head when it is retracted is consequently not the main function of retraction, thus will be an exaptation. As for the difference between the particular two methods of retraction, both Pleurodirans and Cryptodirans use the quick expansion of the neck as a method of predation, therefore the difference in retraction mechanism is not due to a difference in environmental niche.

Head

Most turtles that spend most associated with their lives on property get their eyes looking down at objects in front of them. Some aquatic turtles, such as snapping turtles and soft-shelled turtles, have eyes closer to the top of the mind. These species of turtle can hide from predators in shallow water, where they will lie entirely submerged other than for their eyes plus nostrils. Near their eye, sea turtles possess glands that produce salty holes that rid their body of excess salt taken in from the water they drink.

Turtles have rigid beaks and use their jaws to cut and chew up food. Instead of getting teeth, that they appear in order to have lost about 150-200 million years ago, the upper and lower jaws of the turtle are covered by horny side rails. Carnivorous turtles usually have got knife-sharp ridges for slicing through their prey. Herbivorous turtles have serrated-edged ridges that help them cut through tough plants. They use their tongues in order to swallow food, but unlike most reptiles, they cannot stick out their tongues in order to catch food.

ShellPrimary article: Turtle shellThe upper shell of the turtle is known as the carapace. The particular lower shell that encases the belly is called the plastron. The carapace and plastron are joined together on the turtle's sides by bony constructions called bridges. The inner layer of a turtle's shell is made up of about 60 bones that include portions of the backbone and the particular ribs, meaning the turtle cannot crawl from the shell. In most turtles, the outer layer from the shell is covered simply by horny scales called scutes which are part of its outer skin, or skin. Scutes comprise of the particular fibrous protein keratin that also makes up the scales of other reptiles. These scutes overlap the particular seams between the covering bones and add strength to the shell. Some turtles do not possess horny scutes; regarding example, the leatherback sea turtle and the soft-shelled turtles have shells covered with leathery skin instead.

The particular shape of the cover gives helpful clues about how exactly a turtle lives. Most tortoises have a large, dome-shaped shell that makes it difficult for potential predators to crush the shell between their jaws. 1 of the few exclusions is the African pancake tortoise, which has the flat, flexible shell that allows it to hide in rock crevices. The majority of aquatic turtles have toned, streamlined shells, which help in swimming and diving. American snapping turtles and musk turtles have small, cross-shaped plastrons that give them more efficient leg movement for walking along the particular bottom of ponds plus streams. Another exception is the Belawan Turtle (Cirebon, West Java), which has sunken-back soft-shell.

The color of the turtle's shell may differ. Shells are commonly colored brown, black, or olive green. In some species, covers may have red, lemon, yellow, or grey marks, often spots, lines, or even irregular blotches. One of the most vibrant turtles is the eastern painted turtle, which includes a yellow plastron plus a black or olive shell with red markings around the rim.

Tortoises, being land-based, have rather heavy shells. In contrast, aquatic and soft-shelled turtles have lighter shells that will help them avoid settling in water and swim faster with more agility. These lighter shells possess large spaces called fontanelles between the shell bone fragments. The shells of leatherback sea turtles are extremely gentle because they lack scutes and contain many fontanelles.

It has been recommended by Jackson (2002) that the turtle shell may function as pH buffer. To endure through anoxic conditions, such as winter periods trapped beneath glaciers or within anoxic mud at the end of ponds, turtles utilize two general physical mechanisms. In the situation of prolonged periods associated with anoxia, it has been shown that the turtle cover both releases carbonate buffers and uptakes lactic acid.

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Respiration Turtles

Respiration, for many amniotes, is achieved by the contraction and relaxation associated with specific muscles (i. electronic. intercostals, abs, and/or a diaphragm) attached to an internal rib-cage that can increase or contract the body wall thus assisting air flow out and in of the lungs. The ribs of Chelonians, however, are fused along with their carapace and external to their pelvic and pectoral girdles, a function unique among turtles. This rigid shell is not really capable of expansion, plus by rendering their rib-cage immobile, Testudines have experienced to evolve special modifications for respiration.

Turtle pulmonary ventilation occurs by making use of specific groups of abdominal muscle tissue attached to their viscera and shell that draw the lungs ventrally during inspiration, where air will be drawn in via the negative pressure gradient (Boyle's Law). In expiration, the contraction of the transversus abdominis is the driving force by propelling the viscera into the lungs and expelling air under optimistic pressure. Conversely, the calming and flattening of the particular oblique abdominis muscle pulls the transversus back straight down which, once again, draws air flow back into the lung area. Important auxiliary muscles used for ventilatory processes would be the pectoralis, which is used in conjunction with the transverse abdominis during inspiration, as well as the serratus, which movements with the abdominal oblique associated expiration.

The lungs associated with Testudines are multi-chambered and attached their entire size down the carapace. The quantity of chambers can vary in between taxa, though most often they have three lateral chambers, three medial chambers, and another terminal chamber. As previously mentioned, the act of specific abdominal muscles pulling straight down the viscera (or pressing back up) is what allows for respiration in turtles. Specifically, it is the turtles large liver that pulls or pushes on the lungs. Ventral to the lungs, within the coelomic cavity, the liver of turtles is connected directly to the correct lung, and their abdomen is directly attached in order to the left lung simply by the ventral mesopneumonium, that is attached to their liver with the ventral mesentery. Whenever the liver is pulled down, inspiration begins. Helping the lungs is the particular post-pulmonary septum, which is discovered in all Testudines, and it is thought to prevent the lungs from collapsing.

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Turtles Epidermis and molting

As described above, the outer level of the shell is part of the pores and skin; each scute (or plate) on the shell refers to a single altered scale. The remainder associated with the skin has much smaller scales, similar to the skin of other reptiles. Turtles do not molt their skins all at as soon as as snakes do, but continuously in small parts. When turtles are kept in aquaria, small linens of dead skin may be seen in the particular water (often appearing to be a thin piece of plastic) having already been sloughed off when the particular animals deliberately rub themselves against a piece of wood or even stone. Tortoises also shed skin, but dead skin is allowed to accumulate into thick knobs and dishes that provide protection to parts of the entire body outside the shell.

Simply by counting the rings shaped by the stack of smaller, older scutes along with the larger, newer ones, you are able to estimate the age of a turtle, if one knows how many scutes are produced in per year. This method is not very accurate, partly since growth rate is not really constant, but also since some of the scutes eventually fall away through the shell.

Turtles Limbs

Terrestrial tortoises have short, sturdy feet. Tortoises are popular for moving slowly, simply because of their large, cumbersome shells, which restrict stride length.

Skeleton of snapping turtle (Chelydra serpentina)

Amphibious turtles normally have limbs similar to those of tortoises, except that the feet are webbed plus often have long claws. These turtles swim making use of all four feet in a way similar in order to the dog paddle, along with the feet on the right and left side of the body alternately providing thrust. Large turtles tend in order to swim less than smaller sized ones, and the very big species, such since alligator snapping turtles, barely swim whatsoever, preferring to walk across the bottom associated with the river or river. As well as webbed feet, turtles have really long claws, used in order to help them clamber on to riverbanks and floating logs upon which they bask. Male turtles tend to have particularly long claws, and these appear to be utilized to stimulate the women while mating. While many turtles have webbed feet, some, such as the pig-nosed turtle, have true flippers, along with the digits being joined into paddles as well as the paws being relatively small. These types of species swim in the same way since sea turtles do (see below).

Sea turtles are usually almost entirely aquatic plus have flippers instead associated with feet. Sea turtles take flight with the water, using the particular up-and-down motion of the particular front flippers to create drive; the back feet aren't used for propulsion yet may be used as rudders for steering. Compared with fresh water turtles, sea turtles have got very limited mobility upon land, and in addition to the splash from the nest to the sea as hatchlings, male sea turtles normally never leave the sea. Women must come back onto land to lay eggs. They move very gradually and laboriously, dragging by themselves forwards using their flippers.

Behavior of Turtles

Senses of Turtles are thought to have exceptional night eyesight due to the unusually large quantity of rod cells within their retinas. Turtles have got color vision with the wealth of cone subtypes with sensitivities ranging from the near ultraviolet (UVA) to red. Some property turtles have very poor pursuit movement abilities, which are normally found only in predators that search quick-moving prey, but carnivorous turtles are able to move their heads rapidly to snap.

Turtles Communication

The Arrau turtle has the sizable vocal repertoire.

While typically thought of as mute, turtles make numerous sounds when communicating. Tortoises might be vocal when courting and mating. Various species of both freshwater plus sea turtles emit many types of calls, frequently short and low rate of recurrence, from the time they may be in the egg to whenever they are adults. These vocalizations may serve in order to create group cohesion when migrating.

Turtle Intelligence

See also: Animal cognition

It provides been reported that wooden turtles are better compared to white rats at learning to navigate mazes. Situation studies exist of turtles playing. They are doing, however, have got a very low encephalization quotient (relative brain to body mass), and their particular hard shells enable these to live without fast reflexes or elaborate predator prevention strategies. In the lab, turtles (Pseudemys nelsoni) can learn novel operant jobs and have demonstrated a extensive memory of at least 7. 5 months.

Turtle Mating Strategies

An example of mounting behavior within turtles

Turtles are recognized for displaying a broad variety of mating behaviors, nevertheless , they are not known for forming pair-bonds or for being component of a social group. Once fertilization has occurred and an offspring offers been produced, neither mother or father will provide care for the offspring once is actually hatched. Females generally outnumber males in various turtle species (such as Eco-friendly turtles), and as a result, most men will take part in multiple copulation with multiple partners throughout their lifespan. However, due to the sexual dimorphism present in most turtle species, males must create different courting strategies or use alternate methods in order to gain access to any mate. Most terrestrial varieties have males that are larger than females, and combating between males often establishes a hierarchical order within which the higher up the order an individual is, the better the particular chance is of the person getting access to a potential mate. For many semi-aquatic species and bottom-walking aquatic species, combat happens less often. Males belonging to semi-aquatic and bottom-walking species instead often use their larger size advantage to forcibly mate using a female. In fully marine species, males are often smaller than females plus therefore they cannot use the particular same strategy because their semi-aquatic relatives, which depends on overpowering the females with power. Males in this category resort to using courtship displays in an try to gain mating accessibility to a female.

Combating Between Males Turtles

Saddle back Galapagos tortoise

Wood turtles invariably is an example of a terrestrial species where the males have a hierarchical ranking system based upon dominance through fighting, and it's shown that the particular males with the greatest rank and thus the most wins in fights have the most offspring.

Galapagos tortoises are another example of a types which has a hierarchical rank that is determined simply by dominance displays, and access to food and partners is regulated by this particular dominance hierarchy. Two male saddle backs most usually compete for access to cactus trees, that is their own source of food. The particular winner is the person who stretches their throat the highest, which person gets access to the cactus tree, which may attract potential mates.

Force Mating Turtles

Male (left) and female (right) radiated tortoise

The male scorpion dirt turtle is an example of a bottom-walking aquatic species that depends on overwhelming females with its larger size as a mating strategy. The male methods the female from the back, and often resorts to aggressive methods for example biting the female's tail or hind limbs, followed by a mounting behavior in which the male clasps the edges of her carapace with his forelimbs and hind limbs to hold the girl in position. The male follows this action by laterally waving his mind and sometimes biting the female's head in an attempt to get her to withdraw her head into her shell. This unearths her cloaca, and along with it exposed, the male can attempt copulation simply by seeking to insert his grasping tail.

Male radiated tortoises may also be known to use the force mating technique wherein they use around vegetation to trap or prevent females from getting away, then pin them lower for copulation.

Turtles Courtship Displays

Red-eared sliders are an example of a fully marine species in which the male performs a courtship behavior. Within this case the man extends his forelegs with the palms facing out plus flutters his forelegs within the female's face. Female options are important in this method, as well as the females of several species, such as green sea turtles, aren't always receptive. As such, they've evolved certain behaviors to avoid the male's attempts in copulation, such as swimming away, confronting the man followed by biting, or a refusal position within which the female presumes a vertical position with her limbs widely outspread and her plastron dealing with the male. If the particular water is too superficial to perform the refusal position, the females will resort to beaching on their own, which is a confirmed deterrent method, as the particular males is not going to follow all of them ashore.

Ecology and life history of turtles

Sea turtle swimming

Although numerous turtles spend large quantities of their lives underwater, all turtles and tortoises breathe air and must surface at regular time periods to refill their lungs. They can also spend much or all associated with their lives on dried out land. Aquatic respiration in Australian freshwater turtles is currently being studied. Several species have large cloacal cavities that are covered numerous finger-like projections. These projections, called papillae, have got a rich blood provide and increase the surface region of the cloaca. The turtles can take up dissolved oxygen from the particular water providing a few papillae, in much the same way that fish use gills to respire.

Like some other reptiles, turtles lay eggs that are slightly gentle and leathery. The ovum from the major species are spherical while the eggs of the rest are usually elongated. Their albumen is white and contains another protein from bird eggs, such that it will certainly not coagulate when prepared. Turtle eggs ready to consume consist mainly of yolk. In some species, temperature determines whether an egg cell develops into a man or even a female: a increased temperature the female, a lower temperature causes a man. Large numbers of eggs are deposited in holes dug into mud or even sand. They are then covered and left in order to incubate on their own. Depending upon the species, the eggs will typically take 70–120 days to hatch. When the turtles hatch, they squirm their way to the surface and head toward the water. You will find no known species where the mom cares for her younger.

Sea turtles lay their particular eggs on dry, sandy beaches. Immature sea turtles are not cared for by the adults. Turtles can take many years to achieve breeding age, plus in many cases, breed of dog every few years , rather than annually.

Researchers have lately found out a turtle's organs tend not to steadily break straight down or become less efficient over time, unlike most other animals. It had been found that the liver organ, lungs, and kidneys of a centenarian turtle are usually practically indistinguishable from those of its immature version. This has inspired genetic researchers to get started examining the turtle genome regarding longevity genes.

A group of turtles is actually a bale.

Turtles Diet

A green sea turtle grazing on

A turtle's diet differs greatly based on the environment in which it lives. Grownup turtles typically eat aquatic plants; (citation needed) invertebrates such as insects, snails, and worms; and have been reported to occasionally eat dead marine animals. A number of small freshwater species are usually carnivorous, eating small seafood and a variety of aquatic existence. However, protein is important to turtle growth and juvenile turtles are solely carnivorous.

Sea turtles generally feed on jellyfish, sponges, and other soft-bodied microorganisms. Some species with stronger jaws have been noticed to eat shellfish, while others, for example the green ocean turtle, do not consume meat at all plus, instead, possess a diet mostly made up of algae.

Systematics and evolution of Turtles

Main article: Turtle classification

See|Observe|Notice} also: List of Testudines families

Life restoration of Odontochelys semitestacea, the earliest known turtle relative with a partial shell

"Chelonia" from Ernst Haeckel's Kunstformen der Natur, 1904

Centered on body fossils, the first proto-turtles are thought to have existed in the particular late Triassic Period of the Mesozoic era, regarding 220 million years back, and their shell, which has remained a amazingly stable body plan, is thought to have evolved through bony extensions of their backbones and broad ribs that expanded and grew together to form a complete shell that provided protection at every phase of its evolution, also when the bony component of the shell was not complete. This is backed by fossils of the particular freshwater Odontochelys semitestacea or "half-shelled turtle with teeth", from the late Triassic, which have been found near Guangling in south west China. Odontochelys displays the complete bony plastron and an incomplete carapace, comparable to an early phase of turtle embryonic growth. Just before this discovery, the particular earliest-known fossil turtle ancestors, like Proganochelys, were terrestrial together a complete cover, offering no clue to the evolution of this remarkable anatomical feature. With the past due Jurassic, turtles had radiated widely, and their fossil history becomes easier to read.

Their specific ancestry provides been disputed. It was believed they are the particular only surviving branch of the ancient evolutionary quality Anapsida, which includes groupings like procolophonids, millerettids, protorothyrids, and pareiasaurs. All anapsid skulls lack a temporary opening while all other extant amniotes have temporal openings (although in mammals, the hole has turn out to be the zygomatic arch). The particular millerettids, protorothyrids, and pareiasaurs became extinct in the particular late Permian period plus the procolophonoids during the Triassic.

However , it was later recommended that this anapsid-like turtle skull might be due to reversion rather than to anapsid descent. More recent morphological phylogenetic studies with this in mind placed turtles firmly within diapsids, somewhat closer to Squamata in order to Archosauria.[55][56] All molecular studies have strongly upheld the placement of turtles within diapsids; some place turtles inside Archosauria, or, more frequently, as a sister team to extant archosaurs,[58][59][60][61] though an analysis performed by Lyson et ing. (2012) recovered turtles since the sister group of lepidosaurs instead. Reanalysis of earlier phylogenies suggests that they classified turtles as anapsids both simply because they assumed this classification (most of them studying what sort of anapsid turtles are) plus because they did not really sample fossil and extant taxa broadly enough for constructing the cladogram. Testudines were suggested to get diverged from other diapsids between 200 and 279 million years ago, though the particular debate is far from settled. Even the conventional placement of turtles outside Diapsida cannot be ruled out at this point. A combined analysis associated with morphological and molecular data conducted by Lee (2001) found turtles to be anapsids (though a partnership with archosaurs couldn't end up being statistically rejected).[64] Similarly, a morphological research conducted by Lyson ou al.. (2010) recovered them as anapsids most carefully related to Eunotosaurus. The molecular analysis of 248 nuclear genes from sixteen vertebrate taxa suggests that turtles are a sister group to birds and crocodiles (the Archosauria).[66] The date of splitting up of turtles and parrots and crocodiles was approximated to be 255 mil years back. The most latest common ancestor of residing turtles, corresponding to the split between Pleurodira and Cryptodira, was estimated to have occurred around 157 million many years ago. The oldest conclusive crown-group turtle (member of the modern clade Testudines) is the species Caribemys oxfordiensis from the late Jurassic period (Oxfordian stage). Through utilizing the very first genomic-scale phylogenetic analysis associated with ultraconserved elements (UCEs) to check into the placement of turtles within reptiles, Crawford et al. (2012) also recommend that turtles are the sister group to birds and crocodiles (the Archosauria).

The first genome-wide phylogenetic analysis was completed simply by Wang et al. (2013). Using the draft genomes of Chelonia mydas and Pelodiscus sinensis, the team used largest turtle data set to date in their analysis and concluded that will turtles are likely the sister group of crocodilians and birds (Archosauria). This placement within the diapsids suggests that the turtle lineage lost diapsid head characteristics as it now possesses an anapsid-like skull.

The earliest known fully shelled member of the particular turtle lineage is the late Triassic Proganochelys. This genus already possessed numerous advanced turtle traits, and thus probably indicates many millions of years associated with preceding turtle evolution; this is further supported by evidence from fossil tracks from the Early Triassic of the United States (Wyoming and Utah) plus from the Middle Triassic of Germany, indicating that will proto-turtles already existed because early as the first Triassic. Proganochelys lacked the ability to draw its head into the shell, had a lengthy neck, and had the long, spiked tail finishing in a club. Could body form is similar to those of ankylosaurs, it resulted from convergent development.

Turtles are divided in to two extant suborders: Cryptodira and Pleurodira. The Cryptodira is the larger associated with the two groups and includes all the marine turtles, the terrestrial tortoises, and many of the freshwater turtles. The Pleurodira are sometimes known as the side-necked turtles, a guide to how they retract their own heads into their shells. This particular smaller group consists primarily of various freshwater turtles.