Piscator tenuirostris is known from an incomplete rostrum, the anterior end of a premaxilla, found in Hordle, England, in formations dating to the Priabonian, the final age of the Eocene Epoch.

[3] It was initially described by Colin Harrison and Cyril A. Walker in 1976, and placed in the family phalacrocoracidae.

[2] A similar sample was found in the Late Eocene-early Oligocene Jebel Qatrani Formation in Faiyum, Egypt, but whether this sample represents P. tenuirostris, another Piscator species, or a different phalacrocoracid is unknown.

[1] Piscator was similar to the extant phalacrocoracidae, a piscivorous family of aquatic birds.

[4] Remains were found in the Bracklesham Group in Hordle, England, which dates to the Priabonian, the last age of the Eocene epoch.