Masoncus
{{Short description| Genus of spiders}}
{{Automatic taxobox
| taxon = Masoncus
| authority = Chamberlin, 1949
| type_species = M. arienus
| type_species_authority = Chamberlin, 1949
| subdivision_ranks = Species
| subdivision = 4, see text
}}
Masoncus is a genus of North American dwarf spiders that was first described by Ralph Vary Chamberlin in 1949.{{cite journal| last=Chamberlin| first=R. V.| year=1949| title=On some American spiders of the family Erigonidae| journal=Annals of the Entomological Society of America| pages=483–562| volume=41| issue=4| doi=10.1093/aesa/41.4.483| author-link=Ralph_Vary_Chamberlin}}
Species
{{as of|2019|05}} it contains four species, found in Canada and the United States:{{cite journal| title=Gen. Masoncus Chamberlin, 1949| website=World Spider Catalog Version 20.0| access-date=2019-06-15| year=2019| publisher=Natural History Museum Bern| url=http://www.wsc.nmbe.ch/genus/1425| doi=10.24436/2}}
- Masoncus arienus Chamberlin, 1949 (type) – USA,
- Masoncus conspectus (Gertsch & Davis, 1936) – USA
- Masoncus dux Chamberlin, 1949 – Canada
- Masoncus pogonophilus Cushing, 1995 – USA. Known myrmecophilic association with Pogonomyrmex badius, this spider lives in the nest and feeds on springtails. {{cite book |last1=Tschinkel |first1=Walter R. |title=Ant architecture : the wonder, beauty, and science of underground nests |date=2021 |publisher=Princeton University Press |location=Princeton, New Jersey |isbn=9780691179315 |page=37}}