Horseshoe crab is an example of living fossil because there are fossil extinct of ancestors of horseshoe crabs, and the species still alive today. Horseshoe crab has been around for so long; it has survived mass extinction and it is still around.
<h2>Further Explanation</h2>
Horseshoe crab is considered living fossils because they have existed unchanged for about 445 million years. They are usually not crab; they are not closely related to lobsters or crab. Horseshoe crab is very closely related to spiders and other arachnids.
Generally, there are four species of horseshoe crab that is living today but one out of the species, called Limulus polyphemus can be found in North America. It is found near the Atlantic and gulf coast: from Maine to Mexico.
Horseshoe crab looks is almost the same with their ancient relatives despite the fact that they have been around for so long. Their body structure is tank-like, which is made of:
- A spike tail also known as the telson (used for digging and very fragile)
- A front shell, called the prosoma (this is the large section of the horseshoe crab)
- A back shell, called the opisthosoma (horseshoe crab abdomen, and it is the center section of the shell)
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KEYWORDS:
- horseshoe crab
- telson
- prosoma
- opisthosoma
- species
- crab
