[Natural helminth infection in Sicalis flaveola (Linnaeus, 1766), by Acuaria mayori Lent, Freitas and Proença, 1945 (Nematoda: Acuarioidea) in Brazil]. / Infecção natural em Sicalis flaveola (Linaeus, 1766) por Acuaria mayori lent, freitas e proença, 1945 (nematoda: acuarioidea) no Brasil.

This is the first report of a natural infection in the saffron finch Sicalis flaveola (Linnaeus, 1766) captured in Brazil, with the establishment of a new host record for the acuarioid nematode Acuaria mayori Lent, Freitas and Proença, 1945, previously referred in Cyanocorax chrysops (Vieillot, 1818) from Paraguay and Sporophila caerulescens caerulescens (Vieillot, 1823) and C. cyanomelas (Wied, 1821) from Brazil and Myarchus nuttingi (Ridgway, 1883) from Costa Rica.