Meron

The Merons were a fish-like species who were at war with the Jixen.

Biology
The Merons were light blue-skinned fish-like humanoids with multiple fins and spines on their head and three fingers on each hand. (K9TV: Liberation)

Technology
The Merons used a trident-shaped weapon, which was able to emit a green energy beam. They also had the ability to take a Human form. (K9TV: Liberation)

History
The Merons fought a centuries long war with their sworn enemies, the Jixen, whole planets were destroyed in the conflict. The Jixen were winning the war but they were eventually defeated (K9TV: Liberation) when the Korven turned the tide by supplying the Merons with energy weapons which they then used to obliterate the Jixen homeworld and thus win the war. (K9TV: Hound of the Korven)

In the mid-21st century, a Korven named Lomax from the year 50'000 took control of the British government and created The Department, so the Korven would soon be able take over. He was aided by Thorne, who was originally Human but was implanted with Meron DNA. He was the governor of Dauntless Prison. (K9TV: Eclipse of the Korven) Two Merons disguised as humans also worked in the Department, in Dauntless Prison so they could take DNA from the alien prisoners to create Project: Trojan. They arrived at Gryffen Manor where they gave Alistair Gryffen a component to the Korven Space-Time Manipulator. An accident caused the hound of the Korven, K9 Mark I and four Jixen to be sent through. K9 self-destructed and regenerated into a new form to kill the Jixen. (K9TV: Regeneration)

This Jixen was able to track the Merons down. When K9, Starkey, Darius and Jorjie were investigating the Dauntless Prison, K9 and Starkey encountered the Jixen. Soon after trapping it in a cell, one of the Merons arrived, revealing his true form and attacking K9. When he tried to attack Starkey, the Jixen used its scream and frightened him off. (K9TV: Liberation)

Later that year, Lomax began the Korven invasion of Earth. After the invasion force was destroyed, the completed Trojan was sent by Thorne to destroy K9. K9 used a recording of a Jixen call to cause Trojan's Jixen DNA to fight it's Meron DNA, sending it toppling over and crushing Thorne. (K9TV: Eclipse of the Korven)

Behind the Scenes

 * Only one Meron was shown in his true form in Liberation, however two actors were credited as Merons and Department technicians. In an earlier scene, the Meron from later is seen experimenting on an alien along with another man, who is most likely the second Meron.
 * The Merons also appeared in their Human disguises in Regeneration, despite not being credited.
 * The Merons bear a slight resemblence to the Blowfish though unlike the Merons, it was red in colour.