King crabs are a group of large crustaceans known for their impressive size and distinctive appearance. These formidable marine animals inhabit cold waters, primarily in the North Pacific Ocean. Their unique physical attributes make them easily recognizable among other crustaceans. This article will detail the identifying features of king crabs.
General Physical Characteristics
King crabs are large, with some species reaching a leg span of up to 5 feet (1.5 meters) and weights exceeding 20 pounds (9 kg). Their body plan typically appears somewhat flattened or triangular when viewed from above. Despite being decapods, meaning they have ten limbs, only eight are typically visible and used for locomotion and handling.
These creatures possess three pairs of walking legs that support their large bodies as they move across the ocean floor. A pair of claws, or chelipeds, are located at the front of their body, serving various functions. The fifth pair of legs is much smaller and usually tucked beneath the carapace, used for tasks like cleaning the gills and assisting in reproduction. This arrangement gives the impression of having only six walking legs and two claws.
Distinctive External Features
The prominent external feature of a king crab is its hard shell, known as the carapace. This carapace is typically covered with sharp spines that offer defense against predators. The shape of the carapace can vary but is often rounded or somewhat heart-like.
King crabs exhibit a range of natural colorations, which can vary from reddish-brown to bluish-gray. Many species, such as the red king crab, are named for the bright red color they turn when cooked, rather than their live appearance. Their legs and claws display a characteristic asymmetry; one claw is typically larger and more robust, designed for crushing, while the other is smaller and serves for more delicate handling of food. Additionally, king crabs possess small, stalked eyes and short antennae.
Common King Crab Varieties
Among the recognized king crab species are the Red King Crab, Blue King Crab, and Golden King Crab, each distinguished by specific visual traits. Red King Crabs (Paralithodes camtschaticus) are the largest of the commercially harvested varieties and, when alive, typically display a brownish to bluish-red or burgundy hue. They are known for their spiny shells and can reach a leg span of nearly 6 feet.
Blue King Crabs (Paralithodes platypus) are similar in size to red king crabs but can be distinguished by their color. Live blue king crabs are often brown with royal blue highlights, though they also turn an orange-red when cooked. They are found in specific Alaskan waters and are known for their proportionally large claws.
Golden King Crabs (Lithodes aequispinus), also known as Brown King Crabs, are generally smaller than their red and blue counterparts, averaging between 5 to 8 pounds. Their shells range in color from yellowish-orange to golden-brown. Golden king crabs also tend to have a spikier shell compared to red king crabs and notably thinner legs.