Classification of Phylum Arthropoda

Classification of Phylum Arthropoda

Phylum :- Arthropoda

Characters :-

(i) A pair of externally jointed appendages is usually present in each segment.
(ii) Body is externally covered by thick, tough & chitinous cuticle, forming the exoskeleton.

SubPhylum :- Crustacea

Characters :-

  (i) Head bears five pairs of appendages which comprises of two pairs of antennae & two pairs of
   maxilla.
  (ii) Respiration usually through gills.

Class :- Branchiopoda

Characters:-

                            (i) Trunk appendages are flattened leaf like structure.
                            (ii) Coxa is provided with a flattened epipod.

                             Examples :- Triopes(tadpole shrimp); Daphnia; Artemia;

Class :- Ciripedia

Characters :-

(i)Body enclosed within a bivalve carapace.
(ii) Body is poorly segmented & most lack abdomen.

Examples :- Lepas; Balanus; Sacculina;

Class :- Malacostraca

Characters :-

(i)Body comprises of head, an eight segmented thorax & six segmented abdomen.
(ii) The posterior thoracic limbs being walking legs, the 1st five pairs of abdominal ones forming
swimming organs.

Examples :- Squilla; Hippa; Macrobrachium(prawn); Cancer;

SubPhylum :- Uniramia

Characters :-

  (i)   Appendages are uniramous

       Class :- Diplopoda

Characters :-

(i)Presence of double trunk segments, which are either cylindrical or somewhat flattened.
(ii) Presence of calcified exoskeleton.

Example :- Julus

Class :- Insecta

Characters :-

(i)Head formed by the fusion of 6 segments, typically bears a single pairs of antennae & two pairs of
maxillae.
(ii) The trunk in insects subdevided into three segmented thorax & an abdomen of 11 segments
without walking legs.

Examples :- Lepisma(silver fish); Periplaneta; Carausias(stick insect);Bombyx; Anopheles;

SubPhylum :- Chelicerata

Characters :-

(i)Body divided into an anterior cephalothorax or prosoma, which wholly or partially covered by a
dorsal carapace & a posterior abdomen or opsthosoma.
(ii) Lack of antennae.

Class :- Merostomata

Characters :-

(i)A prominent spike like caudal spine or telson is present at the end of the body.
(ii) Prosoma is covered by a large, horse shoe shaped carapace.

Example :- Limulus