Limulus polyphemus

Common Names: Atlantic horseshoe crab, helmet crab
Category: Sea Creatures
Sub-category: Arthropods

A marine chelicerate arthropod. Despite its name, it is more closely related to spiders, ticks, and scorpions than to crabs. 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'. The smooth shell or carapace is shaped like a horseshoe, and is greenish grey to dark brown in colour. The sexes are similar in appearance, but females are typically 25 to 30 percent larger than the male and can grow up to 24 inches in length (including tail).

Found in the ocean, and often washed up on beaches. During the mating season, they can be abundant on the shoreline.

Edible Notes: In general, not recommended, however the roe/eggs are reported to be edible and are consumed in different parts of the world. All other parts are generally considered poisonous, though there is some debate on the subject. Best to avoid altogether.
Warnings: Not known to be dangerous.