Coraciacarus Dubinin, 1956

Dabert, J. & Alberti, G., 2008, A new species of the genus Coraciacarus (Gabuciniidae, Pterolichoidea) from the huia Heteralocha acutirostris (Callaeatidae, Passeriformes), an extinct bird species from New Zealand, Journal of Natural History 42 (43 - 44), pp. 2763-2776 : 2765

Genus Coraciacarus Dubinin, 1956

The genus Coraciacarus is morphologically a typical gabuciniid taxon with unusually wide host range and may be defined as a euryxenic genus (in the sense of Euzet and Combes 1980). Six morphologically uniform species, including one new species described below, are distributed worldwide among four bird orders: Cuculiformes , Coraciiformes , Musophagiformes and Passeriformes ( Table 1). Also some Coraciacarus species may show relatively wide host ranges, e.g. C. cuculi is reported from 19 species of cuckoos belonging to two families and six genera. Similarly C. meropsi s.l. inhabits 15 species of bee-eaters of the genus Merops . Thus these polyxenic or oligoxenic species (excluding the monoxenic new species) are stenoxenic parasites limited to smaller or bigger groups of closely related host species.

The current generic diagnosis of the Coraciacarus (compiled after Gaud and Atyeo 1975, 1996; de Alzuet et al. 1988) is as follows. In both sexes, two vertical setae vi present; scapular setae se and fine setae si are inserted on one level; setae c2 hair-like; setae c3 dilated and lanceolate; anterior tarsi not longer than double the length of the palps; solenidion S 1 present on genua I and II, absent or inserted basally on genu III; setae cG on genu I setiform and elongated or short and more or less dilated. In males adanal discs well developed with polydentate corolla; genital acetabula positioned posterior to the level of the genital setae g. In females branches of epigynum reach or encompass setae 3a; setae e2 dilated and lanceolate, setae f2 hair-like; genital acetabula posterior to level of setae g and anterior to the level of setae 4a.

The generic diagnosis should be updated after including new species. In the new species setae cG I are thick and long, similar to those in Aetacarus or Gabucinia , and male genital acetabula are inserted laterally to setae g, posterior pair on the level of the setae. We think that these differences do not justify the separation of the new species into its own genus but rather widen the morphological diversity of the genus Coraciacarus . However, this opinion may be changed after more possible hosts of the genus have been analysed, especially of the family Callaeatidae .