Which arthropodans do possess bodies divided in only two distinct parts, namely prosoma/opisthosoma or cephalothorax/abdomen?
2 Answers
Dec 11, 2017
Crustacea and Arachnida .
Explanation:
The classes of arthropods mentioned above have their heads fused with thorax forming cephalothorax.
Lobster is a member of crustaceans.
Hope it helps....
Dec 11, 2017
One is Arachnida, other is Crustacea. Please note horse shoe crab ( Limulus sp.) also has similar distinction.
Explanation:
Great question.
First thing first: body of arthropoda has three parts, head thorax and abdomen.
All three parts are distinct in class Insecta.
In Chilopoda, Diplopoda, Pauropoda, Symphyla, etc thorax and abdomen form a trunk: so there are head and trunk in the body.
When head fuses with thorax, it is either called prosoma as in case of Arachnida, or known as cephalothorax as in Crustacea.
- In class Merostomata, Limulus is only living representative which also has prosoma. The abdomen is called opisthosoma.
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- In case of Crustacea, body is divided in cephalothorax and abdomen; cephalothorax remains dorsally covered by a single calcified exoskeletal element called carapace. Crustacea includes aquatic arthropods with two pair of antennae.
- Most famous members of class Arachnida are scorpions and spiders. The body has prosoma (=head plus thorax) and opisthosoma (=abdomen).
