Classification of Phylum Arthropoda
The Phylum Arthropoda involves 7 classes which are discussed below:
Class 1 Onychophora
- The body is elongated, segmented, and covered with a thin cuticle.
- Peripatus is an important example of the class Onychophora which has characters of phylum Annelida and Arthropoda. Hence it is called connecting link.
- Examples of Onychophora: Peripatus and Principapillatus
Class 2 Crustacea
- The body is divisible into cephalothorax (head+thorax) and abdomen.
- Dorsally, the cephalothorax is covered by a thick exoskeleton carapace.
- There are present two pairs of antennae and a pair of stalked compound eyes.
- Respiration is carried out either by body surface or by gills.
- Example of Crustacea: Crab, Daphnia, Shrimp
Class 3 Insecta
- The body is divisible into the distinct head, thorax, and abdomen.
- The abdomen lacks appendages, the head has a pair of antennae and mouth parts and the thorax has three pairs of legs and two pairs of wings.
- Respiration by tracheae.
- Example of Insecta: Grasshopper, Butterfly, and Honey bee
Class 4 Arachnida
- Body divisible into cephalothorax and abdomen.
- Antennae and true jaws are absent.
- Respiration by tracheae, book-lungs, or book gills.
- Example of Arachnida: Spider, Scorpions, and Mites.
Class 5 Merostomata
- Limulus, (the king or Horseshoe crab) is a good example of class Merostomata which respires through book gills. The king’s crabs are called living fossils. A living fossil is a living animal of ancient origin with many primitive characters.
Class 6 Chilopoda
- The body is divisible into the head and trunk.
- The first pair of legs are modified into poison claws.
- There is a single pair of antennae.
- Respiration occurs by tracheae.
- Excretion takes place by Malpighian tubules,
- Example of Chilopoda: Centipede
Class 7 Diplopoda
- Body is divisible into the head, thorax, and abdomen.
- There is a single pair of antennae.
- Respiration occurs by tracheae.
- Excretion takes place by Malpighian tubules.
- Example of Diplopoda: Millipede
Chilopoda and Diplopoda were earlier included in a single class Myriopoda.
- The body is elongated and metamerically segmented with each segment having one or two pairs of legs.
- Respiration by tracheae. Examples: Scolopendra (centipede), Julus (millepede).
Phylum Arthropoda
Phylum Arthropoda is the largest phylum in the Kingdom Animalia and it includes insects. Arthropoda makes up more than two-thirds of all known species worldwide. The phylum Arthropoda characteristics include jointed appendages, a well-organized body structure with a segmented design, and a tough exoskeleton made of chitin. The Arthropoda body is divided into three sections: head, thorax, and abdomen.
The Phylum Arthropoda examples include insects such as ants, and butterflies arachnids like spiders and scorpions, crustaceans such as crabs, lobsters, and shrimp, as well as myriapods including centipedes and millipedes. In this article, we will cover the Phylum Arthropoda and its classification, and characteristics in detail.
Table of Content
- Phylum Arthropoda
- Phylum Arthropoda Characteristics
- Classification of Phylum Arthropoda
- Respiratory System of Phylum Arthropoda
- Circulation System of Phylum Arthropoda
- Exoskeleton of Arthropoda
- Nervous System of Phylum Arthropoda
- Digestive System of Phylum Arthropoda
- Excretory System of Phylum Arthropoda
- Reproduction System of Phylum Arthropoda
- Senses in Arthropods of Phylum Arthropoda
- Differences Between Annelids and Arthropods