:en:Pseudoniscidae

{{Short description|Extinct family of chelicerates}}

{{Automatic taxobox

| fossil_range = {{fossil range|Silurian}}

| image = 20200923 Pseudoniscidae.png

| image_caption = Restoration of Pseudoniscus roosevelti and Cyamocephalus loganensis

| display_parents = 2

| taxon = Pseudoniscidae

| authority = Packard, 1886

| type_species = †Pseudoniscus aculeatus

| type_species_authority = Nieszkowski, 1859

| subdivision_ranks = Genera

| subdivision =

• †Cyamocephalus
• †Pseudoniscus

| synonyms =

}}

Pseudoniscidae is an extinct family of synziphosurine chelicerates that lived in the Silurian. Pseudoniscidae is classified inside the clade Planaterga, alongside Bunodidae and Dekatriata (chasmataspidids, eurypterids and arachnids). Pseudoniscidae is composed by two genera, Cyamocephalus and Pseudoniscus (the type genus).{{Cite journal|last=Anderson|first=Lyall I.|date=1999-01-01|title=A new specimen of the Silurian synziphosurine arthropod Cyamocephalus|url=http://www.sciencedirect.com/science/article/pii/S0016787899800716|journal=Proceedings of the Geologists' Association|language=en|volume=110|issue=3|pages=211–216|doi=10.1016/S0016-7878(99)80071-6|issn=0016-7878}}{{cite journal|last=Lamsdell|first=James C.|year=2013|title=Revised systematics of Palaeozoic 'horseshoe crabs' and the myth of monophyletic Xiphosura|journal=Zoological Journal of the Linnean Society|volume=167|issue=1|pages=1–27|doi=10.1111/j.1096-3642.2012.00874.x|issn=0024-4082|doi-access=free}}{{cite book|last1=Dunlop|first1=J. A.|title=World Spider Catalog|last2=Penney|first2=D.|last3=Jekel|first3=D.|publisher=Natural History Museum Bern|year=2020|pages=1–296|chapter=A summary list of fossil spiders and their relatives|chapter-url=https://wsc.nmbe.ch/resources/fossils/Fossils20.5.pdf}}