The Myrka is a large amphibious beast genetically engineered by the Silurians. Although more comfortable in the deep sea, juvenile Myrkas at least are able to survive and move around on land, despite not being anywhere as fast and agile as they would be on their natural habitat.
The Myrkas are robust creatures with six limbs (four legs and two arms), a long neck, flattened tail, webbed paws, a fin on their back, and a pair of white eyes. They can attack by generating electrical discharges, although when on land this attack is only effective at short range or if the victim is unfortunate enough to be in touch with a metallic structure that the Myrka is also touching.
Their fully grown form is much larger and closely resembles a sea serpent; it is even possible that sightings of adult Myrkas may have inspired the sea monster legends of old, although there is no concrete evidence of this. As they naturally operate in the ocean, Myrkas are highly vulnerable to light in the UV spectrum. A concentrated beam of UV may even be used to kill them.
- Doctor Who season 21 - Warriors from the Deep (1984)
- The Scales of Injustice, by Gary Russel (1996)
- Big Finish's Doctor Who audio story - "Bloodtide" (2001)