The Kokomopteridae are a family of

eurypterid Eurypterids, often informally called sea scorpions, are a group of extinct arthropods that form the Order (biology), order Eurypterida. The earliest known eurypterids date to the Darriwilian stage of the Ordovician period 467.3 Myr, million yea ...

s, an extinct group of

chelicerate The subphylum Chelicerata (from New Latin, , ) constitutes one of the major subdivisions of the phylum Arthropoda. It contains the sea spiders, horseshoe crabs, and arachnids (including harvestmen, scorpions, spiders, solifuges, ticks, and mite ...

arthropod Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arth ...

s commonly known as "sea scorpions". The family is one of two families contained in the superfamily

Kokomopteroidea Kokomopteroidea is an extinct superfamily of eurypterids, an extinct group of chelicerate arthropods commonly known as "sea scorpions". It is one of four superfamilies classified as part of the suborder Stylonurina. Kokomopteroids have been recov ...

(along with

Hardieopteridae The Hardieopteridae are a family of eurypterids, an extinct group of chelicerate arthropods commonly known as "sea scorpions". The family is one of two families contained in the superfamily Kokomopteroidea (along with Kokomopteridae), which in t ...

), which in turn is one of four superfamilies classified as part of the suborder

Stylonurina Stylonurina is one of two suborders of eurypterids, a group of extinct arthropods commonly known as "sea scorpions". Members of the suborder are collectively and informally known as "stylonurine eurypterids" or "stylonurines". They are known from ...

. Kokomopterids are defined as kokomopteroids with an undifferentiated opisthosoma with a marginal rim. Appendages II-V are spiniferous as in '' Lamontopterus'' and VI is non-spiniferous as in ''

Kokomopterus ''Kokomopterus'' is a genus of prehistoric eurypterid. The genus contains a single species, ''Kokomopterus longicaudatus'', known from the Silurian of Kokomo, Indiana.Dunlop, J. A., Penney, D. & Jekel, D. 2015. A summary list of fossil spiders a ...

''. The Kokomopteridae retains primitive ''

Hughmilleria ''Hughmilleria'' is a genus of eurypterid, an extinct group of aquatic arthropods. Fossils of ''Hughmilleria'' have been discovered in deposits of the Silurian age in China and the United States. Classified as part of the basal family Hughmille ...

''-type prosomal appendages II-IV, unsuited to the sweep-feeding lifestyle used by some of the superfamilies of the Stylonurina (

Stylonuroidea Stylonuroidea is an extinct superfamily of eurypterids, an extinct group of chelicerate arthropods commonly known as "sea scorpions". It is one of four superfamilies classified as part of the suborder Stylonurina. Stylonuroidea, which lived from ...

and Hibbertopteroidea), and were as such likely mainly scavengers.

Genera

Family Kokomopteridae Kjellesvig-Waering, 1966 * ''

'' Kjellesvig-Waering, 1966 * '' Lamontopterus'' Waterston, 1979

References

Stylonurina Silurian first appearances Silurian extinctions Prehistoric arthropod families {{eurypterid-stub