After a new race is encountered by the Borg it is given a designation by which it is catalogued. The Borg do not recognize names, only the numbers which they have assigned.
    Only a few designations of known assimilated races have been revealed.
Species Name Designation
Information
ImageFile
Bolian Unknown A member of the Federation, the Bolians are heavy-set beings - making them ideal drones.
 
Cardassian Unknown Cardassian technology is slightly less advanced then Federation or Klingon tech, however, they too have physiologies which make them perfect drones.
Cataati Unknown A reptilian race, the Cataati were assimilated in late 2371. Their thorium isotope based technology attracted the Borg and they fell quickly. Approximately 30 ships escaped the Borg - carrying only a few thousand people.
 
El-Aurian Unknown The El-Aurian species  was assimilated in the late 23rd century. They had been to many distant parts of the galaxy - including Earth - and thus their knowledge and experiences were sought after by the collective. A few hundred refugees made it to Federation space.
 
Human Unknown A leading member of the Federation, the Human culture revolves around freedom of choice and individual rights. Both of which have been deemed irrelevant by the Borg. Their technology rapidly changes and improves - making them very attractive to the Borg for assimilation. The Collective has tried twice to assimilate this race.
 
Kazon Species 329 When the Borg encountered a small Kazon colony in the Gahn sector they deemed them unfit for assimilation.
 
Klingon Unknown Klingons live for one thing - glory and honour in battle, and whilst these are both primitive values to the Borg the Klingon warlike nature means they have advanced weapons technology and their muscular physiologies make them ideal for combat drones.
Sekari Unknown The Sekari homeworld was assimilated by the Borg in the early 24th century. In less than one hour the Borg had taken the whole planet - some survivors fled into mining caves and were overlooked. When the survivors saw what the Borg had done they resolved themselves to live underground - developing advanced stealth technology to mask their presence.
Skedan Species 4774 A race of telepaths, resembling large kangaroos, their culture was peaceful and the Borg assimilated them for their telepathic abilities.
 
Talaxian Species 218 The Borg happened across a small Talaxian freighter in the Dolmine sector, they rapidly assimilated the ship and its crew of 39. Their limited technological capabilities made their benefit to the collective only in the capacity as reliable drones.
 
Tuktak Species 13 An ancient and very advanced species, the insectoid Tuktak were one of the first races assimilated. The Tuktak yielded the Borg's adaptive technology and personal shields for the drones. 
 
Unknown Species 116 Species 116 are an extremely linguistically capable race. They have the natural ability to grasp the main concepts of an entire language after hearing only a few spoken sentences. Their bodies can easily handle a phaser blast set on full stun without it stopping them. The Borg tried - unsuccessfully -  on several occasions to assimilate the 116s, but they were always one step ahead. When Species 8472 began attacking the Borg the 116s wanted them to win, in the hope that they would be safe afterwards. When the 8472s were defeated the Borg finally caught up with Species 116 and assimilated them. Approximately 10 - 20,000 escaped assimilation.
 
Unknown Species 8472 The only known 'Borg killing' race, species 8472 invaded the Delta Quadrant to seek revenge against the Borg for their invasion of fluidic space. 8472 weapons were able to easily pass through Borg electromagnetic fields and deflector screens, and, when concentrated into a single Bio-ship, the power of several 8472 ships were able to destroy entire planets. The Borg lost many sectors of space to the 8472s, and only defeated them with assistance from Starfleet personnel.
 
Unknown Species 259 Little is known about Species 259 aside from the fact that they inhabited a portion of galactic cluster 3 - a trans-material energy plane intersecting 22 billion omni-cordial lifeforms. The Borg gained autonomous regeneration technology from their assimilation.
Unknown Species 262 Primitive culture assimilated in 2143, their history referred to particle zero-one-zero, the Borg's   designation for the Omega particle, this reference led them to seek it out.
Unknown Species 263 The next species assimilated in the Borg's search for Omega.
Unknown Species 407 A technologically advanced race, their civilization revolved heavily around art and culture. Their resistance was minimal.
 
Vulcan Species 3259 A logic-driven species, the Vulcans also have access to advanced technology, and are themselves leading Federation members. Their emotionless nature would assimilate well into Borg society. Some Vulcans were assimilated during the two Borg attacks on the Federation.
    More species to come later!