Redescription of Serratospiculum seurati Bain & Mawson, 1981 (Nematoda; Diplotriaenidae) from Peregrine falcon (Falco peregrinus Tunstall, 1771).

Air sac nematodes from birds are known for more than 200 years now and Filaria attenuata was the first described species from falcons, owl and corvid birds. The superficial description and the loss of the original material made F. attenuata a species inquirenda. Seurat (1915) redescribed the species with material from lanner falcon and pallid harrier from Algeria and based on this description Bain and Mawson, Rec S Aust Mus 18:265-28, (1981) created a new species, Serratospiculum seurati, by adding some, slightly divergent, measurements. The current paper is based on light and scanning electron microscopy of five male and 10 female S. seurati specimens from a Peregrine falcon that acquired the infection in Pakistan. The length of the slender male and female nematodes varied between 42-70 and 165-221 mm, respectively, spicules of unequal shape and length measured 292-325 and 638-785 µm. S. seurati was also found in Saker, Barbary and crossbreed falcons.