Liigsed

Could you clarify what Liigsed refers to? I’m not sure if it’s a real term in Estonian (for example, a plural form related to joints or another concept), a specific biological group, a historical or cultural term, or a fictional concept. Do you want:

- a concise, neutral wiki-style article about Liigsed as a real term or recognized concept, including definition, classification, distribution, and references; or

- a fictional or hypothetical entry (for a town, species, or organization) written in a neutral encyclopedia style?

If you provide the intended meaning or context, I can draft a concise article under 300 words in plain text.