Paleomerus

Paleomerus Temporal range: Atdabanian, 520–516 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Restoration of P. hamiltoni.
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Order:	†Strabopida
Family:	†Strabopidae
Genus:	†Paleomerus Størmer, 1956
Type species
†Paleomerus hamiltoni Størmer, 1956
Species
†P. hamiltoni Størmer, 1956 †P. makowskii Orlowski, 1983

Paleomerus is a genus of strabopid, a group of extinct arthropods. It has been found in deposits from the Cambrian period (Atdabanian epoch). It is classified in the family Strabopidae of the monotypic order Strabopida. It contains two species, P. hamiltoni from Sweden and P. makowskii from Poland. The generic name is composed by the Ancient Greek words παλαιός (palaiós), meaning "ancient", and μέρος (méros), meaning "part" (and therefore, "ancient part").

Paleomerus is one of the oldest arthropods, being sometimes interpreted as the model of the first arachnomorphs. It is part of the order Strabopida, a poorly known group closely related to the aglaspidids of uncertain affinities, often being ignored by researchers and authors due to the poor preservation and abundance of their fossils. It has been suggested that Paleomerus and the closely related Strabops could be synonymous with each other, since they differ only in the size of the telson (the posteriormost division of the body) and the position of the eyes. These two genera were originally deferred by a hypothetical twelfth segment in Paleomerus, but after the discovery and description of a fourth specimen of P. hamiltoni, it has been shown that this segment actually represents the tail of the animal.