"Hegesidemus writes that in the same city of Iasus another boy also, named Hermias, while riding across the sea in the same manner lost his life in the waves of a sudden storm, but was brought back to the shore, and the dolphin confessing itself the cause of his death did not return out to sea and expired on dry land."
-Piny the Elder, IX.VIII.27-28
Plutarch mentions the coins of Iasos minted in memory of the calamity.
"And the goodwill and friendship of the dolphin for the lad of Iasusa was thought by reason of its greatness to be true love. For it used to swim and play with him during the day, allowing itself to be touched; and when the boy mounted upon its back, it was not reluctant, but used to carry him with pleasure wherever he directed it to go, while all the inhabitants of Iasus flocked to the shore each time this happened. Once a violent storm of rain and hail occurred and the boy slipped off and was drowned. The dolphin took the body and threw both it and itself together on the land and would not leave until it too had died, thinking it right to share a death for which it imagined that it shared the responsibility. And in memory of this calamity the inhabitants of Iasus have minted their coins with the figure of a boy riding a dolphin."
-Plutarch, Moralia, 984.E, Whether Land or Sea Animals Are Cleverer
This coin recalls the death of the boy, Hermias, and his friend, the grief stricken dolphin.
Karia, Iasos, Æ 19mm, 6.4g, circa 200-150 BC, Eupolemos, magistrate
Obv: Jugate heads right of Apollo, laureate, and Artemis to right; behind, dolphin swimming downwards
Rev: Hermias on the back of the dolphin heading right; IAΣΕΩΝ across upper fields, star and ΕΥΠΟΛΕΜΟΣ below
Ref: SNG von Aulock 8096; SNG Copenhagen 415
Where is Iasos? south west edge of modern Türkiye.
Then one comes to Iasus, which lies on an island close to the mainland. It has a harbor; and the people gain most of their livelihood from the sea, for the sea here is well supplied with fish, but the soil of the country is rather poor. Indeed, people fabricate stories of this kind in regard to Iasus: When a citharoede1 was giving a recital, the people all listened for a time, but when the bell that announced the sale of fish rang, they all left him and went away to the fish market, except one man who was hard of hearing.
-Strabo, Geography, 14.2.21
Modified image from Public Domain source on wikiwand.
There is a choral composition by Fazil Say based on the story:
Link: https://youtu.be/ZvatsOA65ys : Hermias - The Boy on Dolphin's Back (Hermias - Yunus Sırtındaki Çocuk)
A statue of Hermias on the dolphin found in an excavation in ancient Nysa, a Carian city in the east of Tralles from the private collection of Mustafa Kenan Özkan, art historian, at Aydın Museum of Ministry of Culture and Tourism of Republic of Türkiye. Ref: Turgut, M. The myth of youth Hermias and his dolphin at Iasos in Caria. Childs Nerv Syst26, 407–409 (2010).
Dolphins and Dolphin-Riders, Brunilde S. Ridgway, Bryn Mawr College, 1970
Beautiful Bodies: from Homer to Winckelmann in J. Philp, A. Stephens & M. Turner, Into the Light: 150 Years of Cultural Treasures at the University of Sydney (Melbourne 2010) 116-155, Michael Turner FSA FLS, 2010, Into the Light: 150 years of cultural treasures at the University of Sydney (pp. 116-155)