A horseshoe crab can live for more than 400 million years.
The horseshoe crab is the only species on earth that has lived more than 400 million years and still retains its original appearance. As one of the best survivors of the four mass extinctions, horseshoe crabs have survived the "darkest period" of biological extinction on earth and have super survival ability.
At its peak, there were hundreds of species of horseshoe crabs. With increased human activities, habitat destruction and overfishing, there are currently only four species of horseshoe crabs left in the world, namely those distributed from China. from the east coast of North America to the Gulf of Mexico, American horseshoe crab and Chinese horseshoe crab, southern horseshoe crab and round-tailed horseshoe crab in Asia.
Chinese horseshoe crab
Chinese horseshoe crab can reach 60 cm in length and weigh 3 to 5 kg. The horseshoe crab is made up of three parts: theThe head and plastron are slightly horseshoe-shaped (hence the name horseshoe crab), the abdomen is hexagonal with spines on both sides, and the tail is a long-tailed sword. Horseshoe crabs look like crabs and are larger than crabs. Although they both have jointed appendages, horseshoe crabs are much less closely related to crabs than to spiders.
The first pair of appendages of horseshoe crabs and spiders resemble claws. They all have four pairs of legs and are taxonomically called chelicerates. The main difference between horseshoe crabs and spiders is that they have a sword-shaped tail. The horseshoe crab has many spiny protuberances at the base of its appendages and surrounds its mouth to chew food, which is why it is also called a limbus.
The horseshoe crab is an ancient creature that lived on earth as far back as the Devonian period more than 300 million years ago. It still retains its shapet can be called an ancient remnant of the ocean. similar to clover. Insects are animals from the same era. When primitive fish were just emerging and dinosaurs had not yet appeared, horseshoe crabs were thriving ocean residents during the Devonian period, 395 to 345 million years ago (some say the Permian period 225 million years ago).
If the environment is suitable and properly maintained, starfish can generally live 3 to 5 years, and some species can even live more than ten years.
As marine creatures, sea stars have special requirements for their living environment. Given the right environment and careful maintenance, starfish can generally live 3 to 5 years, and some species can even live more than ten years. But that doesn't mean that just any starfish couldis easily raised in a home, and its living conditions require careful management.
In order to ensure the healthy survival of starfish, it is necessary to provide a complete environment including sufficient humidity, light, food quality and clean water. Starfish have particularly high demands on water quality. They have to change the water every six months, but only a third is needed to prevent the starfish from adapting to the new water and getting sick.