relictus

Relictus is a Latin adjective meaning “relict” or “left behind.” In scientific naming, it is commonly used to indicate that a taxon or population is a relict—a lineage that persists from a past era and today occupies only a restricted geographic area or ecological niche.

In biogeography and paleontology, relict taxa are remnants of once widespread groups. They may retain ancestral traits relative to related lineages and are often associated with refugia where climate or habitat remains comparatively stable. The concept helps explain disjunct distributions and the survival of ancient lineages alongside more derived relatives.

There is no single diagnostic definition, and the term is used descriptively rather than taxonomically. It complements “living fossil,” a popular but informal label for species such as Ginkgo biloba, Latimeria (coelacanth), Sphenodon (tuatara), and Wollemia nobilis (Wollemi pine). These organisms are cited as relicts because they draw connections to past ecosystems while persisting in the modern world.

In taxonomy, relictus may appear as a species epithet or as part of a genus name to signal a relict status; its use is descriptive rather than indicating a distinct rank. The word reflects ongoing work in biogeography, conservation, and evolutionary biology to understand how ancient lineages survive in today’s changing environments. See also living fossil, refugia, biogeography, and conservation.