Invertebrate Animals

Animals that are grouped by category of spine owners are Vertebrates , and vice versa. Invertebrates belong to the group of animals that do not have a backbone. The following is an explanation of the differences between Invertebrates and Vertebrates, as well as the characteristics of Invertebrates, as well as the phylum of these animals, as well as many more detailed discussions about animals that do not have a backbone.

Difference Between Invertebrates and Vertebrates

Invertebrates or animals Invertebrates are animals that do not have a backbone. Invertebrates include 97% of the members of Kingdom Animalia .

Invertebrates have the opposite meaning of vertebrate animals . Vertebrates have a backbone, while Invertebrates have the opposite. The following is a table of differences between Invertebrates and Vertebrates.


Category Invertebrates Vertebrates

Body Structure No spine Have a spine
2 Circulation System Open in the body Closed in the body
3 Body Features Small and slow moving animals Big and fast moving animals
4 Characteristics Does not have a cell wall and is multicellular Well developed brain, internal skeleton and nervous system
5 Eye Shape Compound Does not have compound eyes
6 Body Symmetry Radial or Bilateral Bilateral
7 Skin Layer 1 layer 2 layers (dermis and epidermis)
8 How to nutrition Parasite or Heterotroph Heterotrophic
9 Group Percentage 95% to 98% 2% to 3%
10 Nervous system Simple and unorganized Complex and specific organs

Characteristics of Invertebrate Animals

Invertebrates have the following characteristics:

  1. Has no spine.
  2. No skull bones.
  3. Does not have a cell wall.
  4. Cannot make their own food (parasites or heterotrophs).
  5. Simple body structure.
  6. The body only consists of the head, chest, and stomach.
  7. Has an outer frame.
  8. Reproduce vegetatively or generatively.
  9. Respiratory system through the skin.
  10. Simple digestive system.
  11. The nervous system is above the digestive tract.

Based on the characteristics above, invertebrate animals can be grouped into the types of insects ( Insecta ) and Worms ( Vermes ). However, the group is then divided into several types, called the animal phylum.

Invertebrate / Invertebrate Animal Group

The types of animals that do not have a backbone are grouped into 8 animal phyla, namely:

  • Annelida

Annelids include the body shape of segmented worms or roundworms, such as: leeches, segmented worms, and others.

  • Arthropods

Booked animals, such as: spiders ( Archnida ), shrimp ( crustacea ), and bees ( Insecata ), and centipedes ( Myriapoda ).

  • Coelenterate

Coelenterata belongs to the Cnidaria group of animals, namely animals that have a sting protection device, and are hollow animals. For example: Jellyfish.

  • Echinoderms

Animals that have prickly skin, such as: starfish, snake stars, and sea cucumbers.

  • Mollusca

Soft-bodied, such as: pearl shellfish, squid, and snails, as well as others.

  • Nemathelminthes

Nemathelminthes is a type of roundworm, has an elliptical body without segments, such as pinworms and stomach worms.

  • Platyhelminthes

It is a group of flatworms, such as Bedfordi flatworms.

  • Porifera

Porifera is a type of animal with a porous or spongy body, such as: Callyspongia Plivivera , Aplysina Fistularis or including yellow tube sponges, and others.

Examples of Invertebrate Animals

The animal population is dominated by the Invertebrate group of about 95% to 98%. The actual number in the Invertebrate group is unknown, but it is estimated that there are tens of millions of members. Most members of the Invertebrate group come from insects.

The following are examples that are included in the Invertebrate group according to their respective phyla:

  • Examples of types of Annelida: earthworms (Scientific Name: Lumbricina ) and leeches (Scientific Name: Hirudinea ).
  • Examples of types of Arthropods: grasshoppers (Scientific Name: Caelifera ), honey bees (Scientific Name: Apis ), and crabs (Scientific Name: Brachyura ).
  • Examples of Cnidaria species: jellyfish (Scientific Name: Scyphozoa ) and sea anemones (Scientific Name: Actiniaria ).
  • Examples of types of Echinoderms: sea lily (Scientific Name: Crinoidea ), sea cucumbers (Scientific Name: Holothuroidea ), sea urchins (Scientific Name: Echinoidea ), and brittle stars (Scientific Name: Ophiuroidea ).
  • Examples of types of Mollusca: devil fish (Scientific Name: Mobulidae ), Pearl oysters (Scientific Name: Pinctada ), sea hare (Scientific Name: Anaspidea ), snails (Scientific Name: Achatina Fulica ), and squid (Scientific Name: Teuthida ) .
  • Examples of types of Nemathelminthes: pinworms (Scientific Name: Enterobius Vermicularis ) and stomach worms (Scientific Name: Nematodes ).
  • Examples of types of Platyhelminthes: tapeworms (Scientific Name: Taenia ) and liver flukes (Scientific Name: Fasciola Hepatica ).
  • Examples of types of Porifera: fresh water sponges and bath sponges.

Invertebrates belong to the group of all animals except the phylum or animal species Chrodata . Examples – examples of invertebrate animals in general, namely:

  • Starfish
  • Worm
  • Octopus
  • Cockroach
  • Shell
  • Spider
  • Snail

The list of other Invertebrate members are: Crustaceans, Rapay, Crickets, Stick Insects, Mantis, Ants, Centipedes, Wasps, and Sponges.

Invertebrate Movement Organs and Their Functions

Invertebrates have organs of locomotion. The organs of motion play a role according to their respective functions, namely:

  • The name of the organ of movement : the belly leg is flat and wide (Animal Name: Snail, Biological Name: Gastropod ).

Function : the main function of the abdominal legs in snails is to move and move around.

  • The name of the organs of motion : legs and wings (Animal Name: Grasshopper, Biological Name: Caelifera ).

Function : serves to make it easier for grasshoppers to move, and jump from one place to another.

  • The name of the organ of motion : muscle fibers, namely Circular, Longitudinal, and Vertical or Oblique (Animal Name: Worm, Biological Name: Lumbricina ).

Function : lengthening the body is a function of circular, and to shorten the body is a function of longitudinal, while vertical or oblique serves to move, flip, fold, and stretch in all directions.

  • The name of the organ of motion : tentacles in the mouth (Animal Name: Jellyfish, Biological Name: Medusozoa ).

Function : serves to move the body of the jellyfish, and catch, and enter food into the body.

  • The name of the organ of movement : the foot. The feet are like flat organs that are removed from the shell at a time, or by opening and or closing the shell suddenly. (Animal Name: Shellfish, Biological Name: Anadara Granosa ).

Function : legs have a function to move the body so that it can move from one place to another.

  • The name of the organ of motion : 10 tantacles, namely in the form of 2 long, 8 shorter. Mantle cavity, and squid fins. (Animal Name: Squid – Squid, Biological Name: Teuthida ).

Function : long tantacles function as predators, and swimmers. Squid can swim backwards using the mantle cavity by spraying water. Squid fins include 2 extensions of the mantle, such as the lobes that function to control or drive balance movements in the body.

After explaining some of the differences between Vertebrates and Invertebrates in various categories or subjects, it turns out that the two types of groups have significant differences. Discussions about Invertebrates will be easier to understand if you pay attention and study examples that fall into the category of the Invertebrate animal phylum.