The Trisect Species:
Giant Spider:

The first species of the Trisect is a giant spider. These are the warriors of the species. The are about six feet high and 13.4 feet across. They can inject venom intotheir enemies, and normally have weapons attachments on their backs. The abnormally big ones that are occasionally born are around one hundred feet tall and almost 300 feet across and carry ground-to-space artillery on their backs. The queens are even bigger than these and can lay several thousand eggs in one week.
Giant Ant:

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The second species is a giant ant. The ants are the resource gatherers of the Trisect species, although they are dangerous close ranged fighters, as their giant stingers can inject a deadly acid into any it injects, which melts the foe from the inside out. They are normally 5 feet high, and 15 feet long. The queen can lay several million eggs in one weeks.
Giant Bee:

The final species in the Trisect, is an incredibly smart species of giant bees. Their intellect far surpasses a G-nome, but their tecnology is several hundred years behind the human race's, they had only just begun space exploration when they were attacked by the Reavers. They are an average 12 feet high and 23 feet long. The queen only lays 47 eggs a week.