In Greek mythology, Echidna was a monster, half-woman and half-snake, who lived alone in a cave. She was the mate of the fearsome monster Typhon and the mother of many of the most famous monsters of Greek myth. Hesiod described her as half a fair-cheeked nymph and half a huge, fearsome serpent, ageless and immortal, dwelling deep beneath the earth. Her parentage and the roster of her monstrous brood vary considerably across the ancient sources.
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I.Genealogy
Echidna's parentage varies significantly across the ancient sources. Hesiod's Theogony presents an ambiguous passage: Echidna is born to a female figure most often read as the sea goddess Ceto, which would make the sea god Phorcys her father. Some scholars instead read the same passage as referring to the Oceanid Callirhoe, which would make Chrysaor (Medusa's offspring) her father.
Other authors proposed different parents. Pherecydes of Athens named Phorcys as her father without identifying a mother. Epimenides, as reported by Pausanias, made her the daughter of the Oceanid Styx and an otherwise unknown figure named Peiras. Apollodorus identified her parents as Tartarus and Gaia (Earth). The Orphic tradition made her a daughter of Phanes, the Orphic father of all the gods.
II.Description
Hesiod portrayed Echidna as a being neither like mortal men nor the immortal gods: "half a nymph with glancing eyes and fair cheeks, and half again a huge snake, great and awful, with speckled skin," who ate raw flesh beneath the earth. He emphasized that she was ageless and deathless for all her days.
Later authors elaborated her monstrous form. Aristophanes gave her a hundred snake heads. Orphic accounts describe a beautiful woman's head atop a serpentine body below the neck, while Nonnus characterized her as hideous and full of horrible poison.
III.Offspring
Echidna was the consort of Typhon, and together they produced many of the great monsters of myth. Hesiod names as their direct offspring Orthrus, the two-headed dog that guarded the cattle of Geryon; Cerberus, the multi-headed hound of Hades; and the Lernaean Hydra. The Theogony is grammatically ambiguous about the Chimera's mother, who may be Echidna, the Hydra, or Ceto.
The parentage of the Sphinx and the Nemean Lion is disputed. Hesiod makes them the offspring of Echidna's son Orthrus by an unspecified female (variously read as the Chimera, Echidna herself, or Ceto). Lasus of Hermione, by contrast, made them direct children of Echidna and Typhon, and Euripides named Echidna as the Sphinx's mother without mentioning a father.
Later authors expanded the brood. Acusilaus added the Caucasian Eagle that ate Prometheus's liver; Pherecydes added Ladon (whom Hesiod had assigned instead to Ceto and Phorcys); Apollodorus included the Crommyonian Sow; and Hyginus listed the Colchian dragon, a "Gorgon" (taken to mean the mother of Medusa), and Scylla. Nonnus described an unnamed, venom-spitting, serpent-footed son, and some sources tentatively linked the Harpies and the sea serpents that attacked Laocoön to Echidna as well.
IV.Cave
Hesiod places Echidna in a cave "beneath the secret parts of the holy earth ... deep down under a hollow rock far from the deathless gods and mortal men," a dwelling appointed for her by the gods at a place called Arima, where she keeps guard. Homer's Iliad refers to the same region as the "couch of Typhoeus."
The location of Arima was debated by ancient geographers. A Cilician hypothesis, favored by Pindar, Callisthenes, and Nonnus, placed it near the Corycian cave around Corycus. A Syrian connection identified it with the region of Mount Kasios (Jebel Aqra) and, per Posidonius, with the Aramaeans. A Lydian/Mysian theory located it in the volcanic Catacecaumene plain near Mount Tmolus and Sardis, a view Demetrius of Scepsis found most plausible. Strabo also records an Italian candidate, the volcanic island of Pithecussae (Ischia) off Cumae, beneath which Pindar said Typhon lay buried. Quintus Smyrnaeus simply locates her cave "close on the borders of Eternal Night."
V.Death
Although Hesiod describes Echidna as immortal and ageless, Apollodorus reports that she eventually died. The hundred-eyed giant Argus Panoptes, a servant of Hera, caught her asleep and slew her, putting an end to her habit of seizing and devouring passers-by.
VI.The Scythian Echidna
Herodotus recounts a separate, half-woman half-serpent creature called an echidna (she-viper) encountered by Heracles in the land that became Scythia. Living in a cave, she had taken Heracles's horses and would return them only after their union, from which she bore three sons: Agathyrsus, Gelonus, and Scythes. Heracles left her a bow and a belt as a test of his sons; only the youngest, Scythes, could meet its conditions, and he became the founder and namesake of the Scythian kings.
VII.Delphyne
Echidna is sometimes connected with Delphyne, the serpent creature slain by Apollo at Delphi. The oldest version, in the Homeric Hymn to Apollo, describes a nameless she-serpent who served as Typhon's foster-mother. Echidna and Delphyne share several features: both are part-maiden and part-snake, both are described as plagues to humankind, and both are closely associated with Typhon and the Corycian cave.
VIII.Iconography
No certain ancient depictions of Echidna survive. Pausanias identifies two standing figures on the sixth-century BC throne of Apollo at Amyclae as Echidna and Typhon, flanked by Tritons, but offers little further description.