A new species of Aquanirmus Clay and Meinertzhagen, 1939 (Phthiraptera, Philopteridae) parasitic on Rollandia rolland chilensis (Lesson, 1928) (Aves, Podicipitidae), with remarks on the external chorionic morphology of the eggs

The authors describe the new species Aquanirmus rollandii sp. n. based on specimens collected on Rollandia rolland chilensis (Lesson 1828), from Argentina, which belongs to the "bahli species group" (sensu Edwards, 1965). Characters of the male, female, and external architecture of the eggs have been used for the descriptions.