Actually, horseshoe crabs don’t use the tail as a weapon at all and there is no poison to be found here. The tail which is called a telson is just used to help it navigate and to turn itself back over should it get knocked onto it’s back.

With that in mind, I wouldn’t want to accidentally step on it with bare feet. The tail is fairly sharp at it’s point and I’m sure you could get a pretty good stab wound from it.

The horseshoe crab has no teeth or even a jaw, so it can’t bite at all, so no chance of getting bit by one. The pincers on the end of it’s legs are not very strong. Just enough to pick up small pieces of food and direct it into it’s mouth. Nothing at all like a real crab which can give you quite a pinch if you let it.

Speaking of crabs, a horseshoe crab is not a crab, but rather a relative of spiders and scorpions. It is a lot friendlier than either of those two cousins. I’m not much into picking up spiders or scorpions that are alive, but a horseshoe crab. No problems there.

Limulus means “odd” and Polyphemus refers to the giant in Greek mythology. It is based on the misleading idea that the animal had a single eye.

Former scientific names include Limulus cyclops, Xiphosura americana and Polyphemus occidentalis.

The horseshoe crab is a ‘living fossil’: forms almost identical to this species were present during the Triassic period 230 million years ago, and similar species were present in the Devonian, a staggering 400 million years ago. Despite their common name, they are not crabs but are related to arachnids (spiders, scorpions, ticks and mites), and are the closest living relatives of the now extinct trilobites.

Horseshoe crabs have three main parts to the body: the head region, known as the ‘prosoma’, the abdominal region or ‘opisthosoma’ and the spine-like tail or ‘telson’. It is the tail that earns this order its name Xiphosura, which derives from the Greek for ‘sword tail’.

The sexes are similar in appearance, but females are much larger than males and the male has a boxer’s glove shaped front claw that is used to hang onto the femail horseshoe crab during spawning.

The carapace is shaped like a horseshoe, and is greenish grey to dark brown in colour. A wide range of marine species become attached to the carapace, including algae, flat worms, molluscs, barnacles and bryozoans, and horseshoe crabs have been described as ‘living museums’ due to the number of organisms that they can support.

On the underside of the prosoma there are six paired appendages, the first of which (the chelicera) are used to pass food into the mouth. The second pair, the pedipalps are used as walking legs; in males they are tipped with ‘claspers’ which are used during mating to hold onto the female’s carapace.

The remaining four pairs of appendages are the ‘pusher legs’, also used in locomotion. The opisthosoma bears a further six pairs of appendages; the first pair houses the genital pores, while the remaining five pairs are modified into flattened plates, known as book gills, that are used in ‘breathing’.

There is a compound eye on each side of the prosoma, five eyes on the top of the carapace, and two eyes on the underside, close to the mouth, making a total of nine eyes. In addition, the tail bears a series of light-sensing organs along its length. A further unique and intriguing feature of this ancient species is that it has blue copper-based blood

Horseshoe crabs are most commonly found in the Gulf of Mexico and along the northern Atlantic coast of North America. A main area of annual migration is Delaware Bay, although stray individuals are occasionally found in Europe.

The other three species in the family Limulidae are also called horseshoe crabs. The Japanese horseshoe crab (Tachypleus tridentatus) is found in the Seto Inland Sea, and is considered an endangered species because of loss of habitat. Two other species occur along the east coast of India: Tachypleus gigas and Carcinoscorpius rotundicauda.  All four are quite similar in form and behavior.

The extinct diminutive horseshoe crab, Lunataspis aurora, 4 centimetres (1.6 in) from head to tail-tip, has been identified in 445-million-year-old Ordovician strata in Manitoba.

If you’ve never seen this, this is something that you should experience.

Also the Horseshoe Crab/Shorebird Festival starts this Friday and runs through Sunday  on the Broadkill River at the Prime Hook National Wildlife Refuge  in Milton, Delaware. You can enjoy barbecue, tours of the refuge and entertainment while learning about the shore bird and horseshoe crab connection. If you want to come join the festivities you can get times and more information by visiting  www.retiretomilton.com

One of the events of the season is the annual horseshoe crab sensus that will be conducted from Maine to Florida by numorous organizations. I’m keeping my fingers crossed that the restrictions that many of the states have placed on horseshoe crab harvesting has helped the horseshoe crab population to rebound from it’s population dip in the last couple of decades.

Photo of a horseshoe crab molting

This is the letter that she sent.

“We found a horseshoe crab on the beach (Buckroe Beach in VA) While
observing the crab on the beach it looked very odd. So I took a couple of pictures.

After looking at a number of websites I still cant understand what I am looking at as all the pics on the sites don’t show anything like what I see.

Where book gills should be there are these organ looking things. (pic 2/ 085JPG) Now do you think something was ripped off of the crab or.. well what is it I am seeing?

My children and I are very interested to know.”

This is horseshoe crab that is about ready to molt. Horseshoe crabs molt their shells up to 18 times during their life. This is just a part of the growing process because the shell does not grow.

The horseshoe crab inflates itself with water (that’s why it looks so
strange) and this helps it break free of it’s shell, this is called molting.
Shorting after leaving the shell (molt) it will form a new shell that it will
keep until it’s ready to molt again.

With a horseshoe crab at the age of the one in the picture, that won’t be for probably another year or so.

The only defense that a horseshoe crab has against predators is it’s hard shell. What they do is bury themselves in the mud or sand which makes it difficult for predators to turn them over or to get a good hold of them.

Horseshoe crabs really don’t have many predators when they are mature, but when they are young they are eaten by many other animals and their eggs are particularly vulnerable. Many shore birds
depend on horseshoe crab eggs for nourishment and to put on weight for their migratory journeys.

There are four known species of horseshoe crabs still in existence; the one that I’m familiar with is the Limulus Polyphemus. This type is found on the entire east coast of North America and in the golf
of Mexico.

These typically get up to 19″ in size and weigh in at about 3 to 5 pounds, at least the ones that I have found. There really isn’t much to these animals and even their shells do not add much to the
weight.

They are served in Asia, although it’s not really all that popular. I’ve been told that they taste a little like king crab. I’m not too sure about that, after all they are more closely related to spiders than to crabs.

Another thing is there is really not much on them to eat. The legs do not get that big, although if you don’t mind working for you meal they are bigger than say crawfish.

I think I’ll keep them off of my menu.