Anteaters

The eusocial arthropoids of Sirius are not ants, and the mammaloids that prey on them are not anteaters, but that it what they were called by the rushed survey team, and that is what stuck.

Neither species truly resembles ants or anteaters. The "ants" are usually about a centimeter long and half as wide, with translucent, slightly shiny exoskeletons. They spend as much time as possible in their underground colonies, hiding from the sun. The "anteaters" have six limbs, but only walk on four. Their front two limbs are asymmetric: one is strong and has large claws to break open colonies, and one is long and dexterous for snatching up ants.

It turns out the anteaters are sentient, something the survey team missed on their first visit. In their defense, the anteaters have no technology. Their social structure, however, is sophisticated, and their politics fast-paced and lethal. Everything revolves around the care and breeding of the ants, which they have domesticated. Leadership is equated with ant farming; their autocrats are expected to "farm" their society like they do their ants.

They have no tools, but their digging claws and organization are enough for them to construct city-scale burrow complexes. They do not use fire, but they practice eugenics. They are breeding themselves to excel even more at their social games, getting smarter and more cunning, yet specialized and incomprehensible. What would happen if this primitive but intelligent species were suddenly introduced to technology? The sector governor has decided to leave that question unanswered.

Shattered Hive

Ghostly pale translucent grubs, chew the mud of an alien planet and huddle together in dark chambers. Once they were larvae, surviving underground until they could metamorphosize into winged insects but cowering in the dark proved a better survival strategy than flying, so now they stay adolescent forever. Once they were solitary, assuming any other life was hostile. Cooperation proved an effective means of gathering food and creating shelter, so their society became tightly bound, and then bond even tighter when the grubs began communicating through an unceasing ultrasonic song, carrying the thoughts of a nascent gestalt mind

Their carefully sculpted clay tower colonies became slumped over mounds and they began to die ever more frequently, from mold, parasites, and confused violence. Yet, in the depths of these mounds, individuals began to experiment with their own creations, churning mud into representations from their dream-like consciousness.

Icthyons

Chemistry and materials science are difficult below the waves, breeding is slow but reliable. Breeding has taken the Icthyons from territorial catfish bullying smaller species for food to gracefully whiskered inheritors of a thousand useful creatures, well-bred and good breeders.

Symbiotes for health, parasites for control. Squid for hunting and barracuda for fighting. A good home is made by waste-eating snails. Octopuses as living tools. Everything is alive or was part of something alive.

The Icthyons have not spared themselves from their great breeding projects. Modern Icthyons are healthier, smarter, more ruthless, and have shorter lifespans than their ancestors, changes introduced through generation after generation of careful matchmaking.

It takes eons to breed stock into a new form. Innovation is virtually impossible, iterative improvement virtually inevitable. Icthyon culture prizes links to the past, and incorporates anything new slowly and thoroughly. Over the course 10,000 years, crab-silk was slowly bred from a disposable and temporary string, to sturdy fabric, to a woven sheets rivaling steel, and so over the course of 10,000 years, knotwork became increasingly sophisticated and fell out of favor, silk fashion became increasingly sophisticated and fell out of favor, and now silk armor is becoming increasingly sophisticated.

Shipbreakers

A strict hierarchy has been maintained, for eons, by the strength of claws against the strength of shells. The ability to kill and resist being killed are all that determines status. Winners devour losers, strengthening their shells and claws with with cannibalized minerals.

They lack whatever that certain something is that allows for true originality. All of their technology is trial-and-error derivations on the scavenged work of others. They would never have left their planet, were it not for the unfortunate crash of a survey vessel. They discovered the wreck, and applied their stubborn form of non-intelligence to it. Within the century, they were starfarers.

Emergency beacons from long lost ships draw victims towards isolated asteroids, and would-be salvagers and rescuers alike find themselves in a rapidly strengthening gravity well, until they are crushed against the surface. Then the shipbreakers will emerge, never engaging in combat, but attacking survivors indirectly, sabotaging life support, setting traps, and waiting. When there are no more survivors, they will disassemble the wreck, reset their trap, and begin to reverse engineer anything new.

Now their shells are steel and their claws are torn from military robots, but they still live by their ancient code: take the strengths of those you kill, hide from those you can't.