what are the first one?
They are decapod crustaceans of the infraorder Brachyura.
Crab
Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen) ( = short, / = tail), usually hidden entirely under the thorax.
where are the walking legs of crustaceans found UNANSWERABLE what are these type of creatures? They comprise of almost 67,000 described species, mostly small and their morphology varies greatly from the largest arthropod in the world – the Japanese spider crab to the smallest the 100-micrometre-long "Stygotantulus stocki". how do they mate? They reproduce sexually as the males decide which females to mate with by dietary differences. are they consumed ? Yes, mainly crabs, lobsters, shrimp, crawfish, and prawns.
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Crab [SEP] Introduction
Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen) ( = short, / = tail), usually hidden entirely under the thorax. They live in all the world's oceans, in fresh water, and on land, are generally covered with a thick exoskeleton, and have a single pair of pincers. Many other animals with similar names – such as hermit crabs, king crabs, porcelain crabs, horseshoe crabs, and crab lice – are not true crabs.