''Eucastor'' is an extinct genus of beaver-grouped rodents. Based on the available evidence of the foramina, ''Eucastor'' most likely is closely related to ''Castor'', but not in its direct lineage.

References

* McKenna, Malcolm C., and Bell, Susan K. 1997. ''Classification of Mammals Above the Species Level''. Columbia University Press, New York, 631 pp. Prehistoric beavers Prehistoric rodent genera Taxa named by Joseph Leidy {{paleo-rodent-stub