Obelisk (biology)
An obelisk is a microscopic genetic element that consists of a type of infectious agent composed of RNA. Described as a "viroid-like element", they consist of RNA in a circular rod shape without any protein shell coating.
Obelisks were identified in 2024 through computational analysis of vast genetic datasets. Their RNA sequences are entirely novel, and their placement within the tree of life remains uncertain as they do not appear to have a shared ancestry with any other life form, virus, or viroid. Obelisks are currently classified as an enigmatic taxon, forming a distinct phylogenetic group.