Segesta is out of Antonoe (First Defence), a Grade 1 winner in the US and a Group winner in France, who took the Gr.3 Prix d'Aumale and was placed in the Grade 1 Diana Stakes. Antonoe is also the dam of Salamis (Speightstown), a Grade 1 winner, giving her two top-level winners in the same weekend.

Second dam Ixora (Dynaformer) is also the dam of Upbeat Mood (Mizzen Mast), whose produce includes Light Mood (City Light), Listed-placed in France.

Third dam Imroz (Nureyev).

This female line traces to All at Sea, winner of the Gr.1 Prix du Moulin de Longchamp, and the wider family includes the stakes-placed West Beach (Omaha Beach).

Antonoe has a 2-year-old filly, Directive (Gun Runner), and a yearling full-sister to Salamis. She was barren to Munnings for 2025 and was covered by Justify for 2026.