The body of the largest vertebrate animals is not a mystery to most people: it is known to have a skeleton, vital internal organs (heart, brain, etc.), a dermis of variable characteristics and organs through which the five senses are manifested, among other characteristics.
However, have you ever wondered what the morphology of invertebrates is like? Then you need to know all about the animals with exoskeletons, names and examples. Don't miss this article on our site!
What is the exoskeleton?
The exoskeleton is an external structure that covers the body of various animals, including arthropods. It is characterized by being resistant but flexible This structure is made up of different substances depending on the subphylum to which the animal belongs: chitin for insects and fungi, calcium in molluscs and corals or silica in diatoms among other components.
In turn, the exoskeleton is made up of three structures:
- Cuticle: non-cellular layer secreted by the hypodermis, arthropods are able to shed this layer in order to grow.
- Hypodermis: cellular structure that generates the cuticle and creates the necessary conditions for its shedding.
- Basement membrane: innermost non-cellular layer of the exoskeleton, responsible for supporting the muscles.
Now, what are the functions of the exoskeleton? Handles:
- Protect and support the muscles and internal organs.
- Isolate the animal from external agents, such as humidity and dryness.
- Store Substances that give many species brilliant colors.
Now then, some species, in addition to having an exoskeleton, also have an endoskeleton.
Classification of arthropods
The arthropod phylum contains the greater number of species than any other in the world. They all have exoskeletons, but what are these animals? To find out, you must know the classification of arthropods:
Protarthropoda
They have primitive legs, a head and an abdomen. They can be terrestrial or aquatic. They are included in this superclass:
- Arachnids: includes spiders, ticks, mites, scorpions, scorpions, among others. In total it includes more than 30,000 different species.
- Pycnogonida: Includes 50 species of sea spiders, which usually live on top of the bodies of other animals.
Euarthropoda
Includes the superclass Mandibulata, where animals, most of them terrestrial, that have jaws are classified. In addition, the species have well-formed antennae, legs and jaw pieces. It covers the following classes:
- Insect or insects: they have a well-defined head, thorax and abdomen. They live in terrestrial or aquatic environments and some have wings. The different species present a multiplicity of characteristics and peculiarities.
- Crustaceans: they have a rigid exoskeleton due to calcareous substances. They live in fresh or s alt water and house a wide variety of species with multiple appearances, from crabs and crabs to mealybugs.
- Myriapods: develop an elongated trunk that makes them similar to worms, but with a different head.
In turn, the subclass of the Myriapods is divided into:
- Diplópodos: they are the millipedes or congorochos. They have jaws, an elongated body and several legs.
- Chilopoda: includes centipedes and scolopendras. Similar to diplopods, they have a more elongated body.
- Symphylos: elongated species similar to chilopods, but smaller and with antennae.
- Pauropoda: These are terrestrial worms that like to live in humus, have antennae and have tracheal breathing.
Animals with exoskeletons
Now that you know all about this exterior structure, here are some animals with exoskeletons:
1. Mite
Of the subclass Acari, these are parasitic arachnids of other animals. There are terrestrial and aquatic species, and their diet is varied: hematophagous, detritivorous and herbivorous. Different species are capable of transmitting diseases or becoming a plant pest.
two. Crabs
There are many types of crabs, but in general we are talking about five-legged crustaceans, a body with a strong shell and claws that allow them to defend themselves and catch their prey. They live on the seabed, where they walk to find their food, which is mainly made up of smaller animals.
3. Bees
Bees are insects that are widely distributed on planet Earth. They are organized in colonies with well-defined hierarchies and are very important in the pollination process of thousands of plant species.
4. Centipede
Under the name of centipedes focuses on more than 3,000 species of arthropods that are characterized by having an elongated body divided into segments, multiple legs, antennae and powerful jaws. They are predators and hunt insects, worms and snails
5. Sea spiders
They have eight legs that they use to move, which is why they are compared to land spiders. They easily blend into the seabed and have a body with long, thin limbs.
What is the endoskeleton?
It is an internal structure that protects the organs, allows the muscles to strengthen, gives shape to the animal's body, allows movement and protects the nervous system. All vertebrates have an endoskeleton, so the most common animals have these structures.
One difference between the exoskeleton and the endoskeleton is that the latter does not "shed", but instead grows with the individual it belongs, but does not need to be discarded to perform this function. Furthermore, it develops from the time the organism is an embryo.
On the other hand, endoskeletons are characterized by having a vertebral column or backbone made up of discs, which protect the nervous system and connect to the skull and brain in most species.
Animals with endoskeleton
There are thousands of species that have this structure that allows them to protect their organs and strengthen the shape of the body. These are some of the animals with an endoskeleton:
1. Cephalopods
Commonly known as octopuses and squids, cephalopods have inhabited the seas since the Carboniferous. They are characterized by having tentacles and a flexible body with a gelatinous texture. They feed on other animals.
two. Fishes
Most fish have an endoskeleton that protects their internal organs and provides the muscles with ideal support for swimming. For this reason, the endoskeleton of fish includes part of the fins and tail in many specimens.
3. Urochordates
They are a phylum of marine animals that has more than 3.000 species. They have tubular, elongated or even microscopic bodies, but they have in common a primitive nervous and circulatory system Despite this, they have a simple exoskeleton that contains blood cells and supports muscles.
4. Vertebrates
All vertebrates, whether marine, terrestrial, flying or freshwater, have an exoskeleton that protects their organs, contains the nervous system and provides support to the muscles. Among the vertebrates we find the following animals:
- Amphibians
- Reptiles
- Birds
- Mammals
- Cartilaginous fishes
- Fish with fins
Human beings are also in this classification.
Animals with exoskeleton and endoskeleton
In the diverse fauna that inhabits the planet, there are some animals with exoskeleton and endoskeleton. Do you recognize these species?
1. Armadillos
Armadillos are land mammals and therefore have an endoskeleton inside their bodies. However, these animals are also characterized by having an external armor made up of bony plates, which serves as a means of protection.
two. Pangolins
Pangolins are mammals that are distributed in Asia and Africa, where they feed on ants and termites. In terms of its appearance, it is similar to armadillos since, in addition to being a vertebrate, it has an external armor made up of rigid plates.
3. Turtles
Sea and aquatic turtles have an exoskeleton that facilitates their recognition: the shell The shell protects the organs and, at the same time, it represents a kind of "home" for the turtle, where it can take refuge to rest or avoid predators.
