A problematic entry. Its immediate source, Harpokration s.v., was generated by Aeschines 3.122, where mention is made of the Thyteion (sic: "Sacrificing-place") at Delphi. Harpokration does, though, proceed directly from citing Aeschines to calling Thystion "a city of Aitolia"; for this Didymus is cited, who in turn is said to have cited Nikandros of Kolophon, Matters Aitolian (FGrH 271-2 F3). Perhaps Aitolian Thesteia (Barrington Atlas map 55 grid A3)?