Mirelurk (Fallout 4)

Mirelurks are creatures ecountered in the Commonwealth in Fallout 4.

Background
Mirelurks are descended from Chesapeake Bayhorseshoe and blue clabs. The full scientific classification of the mirelurks is kingdom:Animalia, phylum: Arthropodia, subphylum:Crustacean/Chelicerata, class:Merostomata/Malacostraca, while order, family, and genus are left undetermined due to their mutation. The subphylum and class are disputed as horseshoe crabs and blue crabs both evolved into mirelurks, due to their DNA/RNA samples having markers from two different subphyla and classes. Regardless, the missing order, family, and genus are later filled in by scientists: Scylla serrata horrendus. The crustacean mirelurks appear to have a symbiotic relationship with a species of mutated snapping turtles called the "mirelurk kings". These "kings" are similar to the lakelurks of Mojave Wasteland, which do not share a symbiotic relationship with any crab species.

Characteristics
An aquatic creature that appears in Fallout 4. This specimen in particular resembles a mirelurk hunter, but also differs in several aspects, such as seen with their legs. This specimen also walks in a mixed crab/spider-like motion, which is atypical of mirelurk variants documented so far. Of course, this may be a kind of "reboot" of the mirelurk's design, in an attempt to make them look more crab-like. Mirelurks also appear to deal radiation when killed in close quarters.

Mirelurks will bury themselves in dirt or mud, with the only visual indication that they are present being the rounded backs of their shells, which resemble large, smooth rocks from a distance. VATS will be able to spot them from a distance when used.

Mirelurk hatchling
When approaching a mirelurk nest, attacking or stealing mirelurk eggs will force nearby eggs to hatch prematurely, revealing these small crab like creatures. The mirelurk queen can spawn several hatchlings to attack the player.

Mirelurk killclaw
Powerful mirelurks, which stands by their "legendary killclaw" at Cutler Bend.

Mirelurk queen
The mirelurk queen is a new mirelurk variant. The queen is considerably larger and more dangerous than her children and inflicts more radiation on the player character. The mirelurk queen's acidic spittle rapidly damages anyone caught in it and she can spawn new hatchlings. Crippling her spouts will prevent her from using her acid attack. She benefits from the same resistance as the regular mirelurks : an incredibly thick shell but a very soft skin. It can take up to three shots from the Fat Man to kill her but half a cartridge clip from a minigun can be enough to take her down. One occupies The Castle and is fought when the Minutemen retake it, another occupies the Murkwater construction site, another can be found at Nahant Chapel, and one occupies Spectacle Island.

Mirelurk hunter
This Mirelurk seems to have mutated from the local lobster population due to the body structure.

Mirelurk king
Powerful mirelurks, which stand by their "legendary king" at Cutler Bend. Can also be found in the water close by Rook family house.

Appearances
Mirelurks appear in Fallout 3 and Fallout 4.

Behind the scenes
The mirelurk model was created by Jonah Lobe, with their Fallout 4 model bearing close similarities to the Garthim from the movie The Dark Crystal.

Bugs
Receiving acid damage from a mirelurk may cause the skin effect to remain forever.