Which of the following creatures does NOT belong to an Arthropoda phylum?

Key Points

• Most of the insects like ants, cockroach, mosquito, crabs, spiders, scorpions, sea spiders and mites etc., fall under the phylum Arthropoda.
• Snail, Octopus (Devilfish), sepia (cuttlefish) are examples of Mollusca which is the second-largest phylum after Arthropoda.

 Important PointsPhylum Arthropoda is the largest phylum in the animal kingdom.

• Arthropods have jointed limbs.
• Their body is segmented into three regions - Head, Thorax and Abdomen

Some important characteristics of this phylum are:

• Segmented bodies.
• Joined appendages.
• Open circulatory system.
• They make up about 80 per cent of the known species of animals.

Additional Information

• Mollusca is the second-largest animal phylum. They are terrestrial or aquatic.
• They exhibit an organ-system level of organization.
• They are bilaterally symmetrical, triploblastic, coelomate animals. 
• They have an open circulatory system and kidney-like organs for excretion.
• The anterior head region has sensory tentacles.
• The mouth contains a file-like rasping organ for feeding, called a radula.
• They are usually dioecious and oviparous with indirect development.
• The body is covered by a calcareous shell and is unsegmented with a distinct head, muscular foot, and visceral hump. A soft and spongy layer of skin forms a mantle over the visceral hump.
• Examples are octopus, snails, and mussels.