In Jim Butcher's Codex Alera series, there is an "alien" race known as the Vord. The Vord is known for its powerful reproduction rate and its adaptability, all led by the Queen. What forms of the Vord existed and were described in detail?
From Codex Alera Wiki
Forms of the Vord
Before the main invasion force appears, the Vord will send out small rodent-size parasites. These parasites take over the host and, during the initial phase, will just lead the host back to the Vord nest. The Marat refer to the hosts as the "taken". Once they're taken, there's almost no hope of ever recovering the original person's consciousness. If the host could previously control furies, this ability is lost until furycrafting is used against the taken host. When fighting, the host will have little concern for its own life and will ignore most pain.
The Vord warriors vary depending on the target of the invasion. The parasitic version returns samples of their target and the warriors assume a similar, but different form. They don't use any weapons directly, but are incredibly strong, fast, have swordlike appendages, and are naturally extremely well armored. The warriors are known to have a weakness on their back - a croach-filled sac. It acts as a sort of breathing apparatus. Once destroyed, the warrior will soon smother to death.
The Vord queens also vary. They are extremely fast, strong, and tough. During an invasion, a queen will quickly create a nest and send out two other queens to form their own nests. Queens are known to have telepathic abilities and can, if within a certain range, control enemies that are not yet under control of the parasites.
Keepers, also known as the "Wax Spiders," are dog-sized spider-shaped creatures. They maintain, feed, and feed off of the croach. If any portion of the croach becomes damaged, the Wax Spiders quickly appear to investigate the site and will attempt to kill any potential foes. They are known to see in infrared, but can also switch to the visible spectrum.
Little is known about the Vord. They are described repeatedly as an "alien" race, but no one knows where they come from. The Vord are originally found in Alera in the Wax forest, where their Queen slumbered. Events were set into motion by Tavi and Kitai which awakened the queen, and caused the Vord invasion. According to Marat tradition, they are shapeshifters. When they come, they possess members of a sentient race, consuming their souls and transforming them into the Taken. The normal vord scouts (called Keepers) have the appearance of large spiders and see in infrared vision. They feed on a translucent, waxy substance called croach, and resided in dormancy in the Wax Forest before they were awoken by Tavi and Kitai. After the Vord queen was awakened, she began producing members of the Vord warrior form; these vord warriors tend to take on the characteristics of the civilization that they are assaulting, and have colossal reserves of strength. When facing the Alerans, they take on humanoid forms, and emulate the Knights. For example, one type of Warrior Vord has a humanoid body, dragonfly-like wings, and two blade-like arms the same length as a legionnaire's Gladius (the Legion weapon of choice) and thus resemble a Knight Aeris. In another instance, they take on the characteristics of the Canim Warrior caste. While they can be killed by conventional methods, the most effective way to kill a vord warrior is to burst the large, croach filled bubble on its back. At the start of each vord uprising, there is a primary queen; this queen rapidly forms a nest, and spawns two additional queens who depart to form separate nests; each queen is capable of creating more queens. Although in "Princeps' Fury", it is discovered that the primary queen birthed sterile queens in the Canim lands. The Keepers, venomous, spider-like creatures the size of dogs, maintain the croach; without the croach the vord can not survive, for it acts as both air and food. Keepers take living creatures into the croach and they are slowly dissolved into it. The vord's main objective appears to be to make all things like itself; in pursuit of this goal, the three queens will each occupy different areas of the places (in Carna) they wish to "infect". After the events in the book "Cursor's Fury", the prologue states that the Vord had taken over the savage Canim's homeland. After events in "Princeps' Fury", the Vord queen is described as looking like Kitai but greenish; this probably has something to do with the events that happened between Kitai and Tavi when they sought the Blessing Of The Night in Calderon many years before and awoke the creature. After First Lord's Fury the Vord in Alera are left in disarray and slowly being exterminated, though wild Vord who learned to survive do remain. The Vord in Canea are left as a future threat to the realm, unifying the surviving races against the common enemy.
The forms were:
There is a good summary here