Background: The common waxbill, Estrilda astrild (L., 1758) (Passeriformes: Estrildidae) is a small passerine bird native to Sub-Saharan Africa that has been introduced into several regions of the world.
Results: In the present paper, eight mite species (Acariformes) are reported from this host from Brazil, including three species new to science: Montesauria caravela n. sp., M. conquistador n. sp. (Proctophyllodidae), Trouessartia transatlantica n. sp., T. minuscula Gaud & Mouchet, 1958, T. estrildae Gaud & Mouchet, 1958 (Trouessartiidae), Onychalges pachyspathus Gaud, 1968 (Pyroglyphidae), Paddacoptes paddae (Fain, 1964) (Dermationidae) and Neocheyletiella megaphallos (Lawrence, 1959) (Cheyletidae). Comparative material from Africa was also studied.
Conclusions: These mites represent at least three morpho-ecological groups regarding their microhabitats occupied on the bird: (i) vane mites (Montesauria and Trouessartia on the large wing and tail feathers); (ii) down mites (Onychalges); and (iii) skin mites (Paddacoptes and Neocheyletiella). On one bird individual we found representatives of all eight mite species. Although the common waxbill was introduced to the Neotropical region almost two centuries ago, we demonstrate that it still retains its Old World acarofauna and has not yet acquired any representatives of typical Neotropical mite taxa.
Keywords: Acari; Biodiversity; Biogeography; Feather mites; Neotropics; Systematics.