Surdelina (f)
(with) definite article: laBeing the only one of all my sources who mentions it as a synonym of Surdulina, Leydi enigmatically (and oddly) treats it, exclusively, as a "primary" name in his text.
NB: ➺ homonyms & similar terms, Sardellina & Sardëllina, Serdellina, Sordelina &c., and Sourdeline and related terms.
Leydi, Roberto: La zampogna in Europa. Como, 1979, p.140.
Scaldaferri, Nicola: Zampogna a chiave e surdulina a Terranova e nell'area del Pollino: morfologia e repertori musicali. In: Le zampogne a Terranova di Pollino... (2015), p.30.