Ylva Karjanzdottar Andelarion (born in Hurmu in 1450, died in Caligae in 1502) was the first wife of Rashid Arsalani (later Kaiser Ayreon) from 1469 until her death, and the first and only countess consort of Elwynn (from c. 1500 until her death in 1502). During the countship of her husband as well as posthumously, she was known as Lady Andelarion, The Countess of Elwynn. The bailiwick of Andelarion is named after her and her tribe.
Ylva belonged to the Andelarion tribe of Hurmudans, and was the daughter of Karjan Udarson and Elja Ådar Andelarion.
She met Rashid in 1465, when both were 16 years old, and they married in 1469 in a private ceremony. The couple divided their time between Babkha and Hurmu. She had three children, two sons, Rashid Karyandzadeh in 1472 (named so after his father and maternal grandfather) and Eskender Kashmal 11 months later the same year, and one daughter, Nour, born in 1479. In 1483, Nour died from a congential heart condition. The same heart condition took Ylva's life in 1502. Rashid would later say that Ylva was the love of his life, despite marrying twice later in his life.