Devonian arthropods

Mimetaster is an extinct genus of marrellomorph arthropod. The type species, Mimetaster hexagonalis is known from the Lower Devonian (Pragian-Emsian) Hunsrück Slate, and amongst the most common arthropods from the locality, with over 120 specimens including three juveniles.

Dolichopteridae is an extinct family of eurypterids that lived in the Silurian and Devonian periods.

Chasmataspidids, sometime referred to as chasmataspids, are a group of extinct chelicerate arthropods that form the order Chasmataspidida. Chasmataspidids are probably related to horseshoe crabs (Xiphosura) and/or sea scorpions (Eurypterida), while more recent studies suggest that they form a clade (Dekatriata) with Eurypterida and Arachnida. Chasmataspidids are known sporadically in the fossil record through to the mid-Devonian, with possible evidence suggesting that they were also present during the late Cambrian. Chasmataspidids are most easily recognised by having an opisthosoma divided in

Rhyniella is a genus of fossil springtails (Collembola) from the Rhynie chert, which formed during the Pragian stage of the Early Devonian. One species has been described, Rhyniella praecursor. For some time it was believed to be the only hexapod from the Early Devonian ( )