Pliny the Elder [1st century CE] (Natural History, Book 9, 29): [Book 9, 29] Nowadays the first place is given to the wrasse [scaro], which is the only fish that is said to chew the cud and to feed on grasses and not on other fish. It is especially common in the Carpathian Sea; it never of its own accord passes Cape Lectum in the Troad. Some wrasse were imported from there in the principate of Tiberius Claudius by one of his freedmen, Optatus, Commander of the Fleet, and were distributed and scattered about between the mouth of the Tiber and the coast of Campania, care being taken for about five years that when caught they should be put back into the sea. [Book 32, 5] Wonderful too appear to me the characters of fishes given by Ovid in his book entitled Halieuticon: how the scarus, caught in a weel, does not burst out to the front, or thrust his head through the osiers that imprison him, but turns round, widens the gaps with repeated blows of his tail, and so creeps backwards. If by chance his struggles are seen by another scarus outside, he seizing the other's tail with his teeth helps the efforts to burst out. - [Rackham translation]

Saint Ambrose [4th century CE] (Hexameron, Book 5, 5.12): For that reason their [fish] teeth are closely-packed and sharp so as to be able to bite and dispatch quickly their food and swallow it easily without delay. Hence, they do not chew the cud, as the scarus is said to do, if we are to believe those who either by chance or design have come to know such matters. - [Savage translation, 1961]

Isidore of Seville [7th century CE] (Etymologies, Book 12, 6:30): The escarus is so named because it is said to be the only one to ruminate its food [esca]; for the other fish do not ruminate. People say that this is a clever fish, for when it is enclosed in a wicker trap, it does not break through with its brow or thrust its head through the opposing twigs, but, turning around, with repeated blows of its tail it widens an opening and so goes out backwards. If by chance another escarus sees its struggle from the outside, it helps its efforts to break out by seizing the tail with its teeth. - [Barney, Lewis, et. al. translation]

Thomas of Cantimpré [circa 1200-1272 CE] (Liber de natura rerum, Fish 7.83): Scaurus is a fish, the flesh of which is quite delicious to eat. This fish alone among all kinds of fish, as Ambrose says, is said to chew the cud: for it does not have sharp and fixed teeth in its mouth, as all kinds of fish have. These were first brought from foreign lands to Rome, and being thrown into the Tiber, they multiplied. Of the scauro, Isidore says, that it is so ingenious, that when it sees that it is caught in a trap, it does not endeavor to break out with its head, nor to stick its head into the wicker canes, but with frequent blows of its tail it tries to loosen the doors, and so tries to escape; if by chance another scaurus sees it struggling from the outside, it seizes its tail with its teeth and helps it in its efforts to break out. This is what the scaurus does when caught in nets; for it is trying to get out backwards. - [Badke translation/paraphrase]

Bartholomaeus Anglicus [13th century CE] (Liber de proprietatibus rerum, Book13.26): Also in lyke wise it is sayd there of a Fish which is called Estaurus: For among Fish, onelye that Fish cheweth his kudde. And it is sayd that this Fish is right wittye. For when he knoweth that hee is entered, and is within the daunger of the Fishers ginne, hée reeseth not foorth headlong, neyther putteth his head betweene the rowles of the gunne: but he beateth fast on the other with his tayle, and beginneth to make him away with breaking and renting of roddes, and so pasieth backwarde. And if it happen that another Fish of the same kinde seeth his doing, and how he travaileth for to break out: he busieth to helpe him, and taketh his tayle in his mouth, and helpeth as hée maye to drawe him out, and deliver him of the ginne. - [Batman]