Nematodes and acanthocephalans of buzzards (Buteo spp.): Checklist of species in Europe and new host-parasite associations in Romania.

Various species of nematodes and acanthocephalans are frequently encountered in birds from the genus Buteo. In Romania, three species of buzzards are present: the Eurasian buzzard (Buteo buteo), the long-legged buzzard (B. rufinus), and the rough-legged buzzard (B. lagopus). This study represents the first comprehensive research on roundworms and acanthocephalans parasitizing birds from genus Buteo in Romania. Between 2017 and 2024, 88 Eurasian buzzards, two long-legged buzzards, and three rough-legged buzzards which were found dead were collected from various localities in Romania. All specimens were necropsied and examined for nematodes and acanthocephalans, which later on were divided equally and preserved in 100 % ethanol for molecular identification and 4 % formaldehyde for morphological identification. Morphological identification revealed three species of acanthocephalans from the family Centrorhynchidae and 12 species of nematodes belonging to seven families: four species from Capillariidae, two species from each Tetrameridae and Toxocaridae, and one species from each Acuariidae, Habronematidae, Physalopteridae, and Syngamidae families. This study provides new data about the diversity of nematodes and acanthocephalan parasitizing B. buteo, B. lagopus and B. rufinus in Romania. To our best knowledge, this study reports B. lagopus as a new host for Eucoleus contortus, Procyrnea leptoptera, and Microtetrameres sp. and B. rufinus as a new host of P. leptoptera.