Ticks and Novel Chigger Mite Species on Passerine Birds in Southeastern Arizona

We document the combined occurrences of one immature tick species (Amblyomma cf. triste), 2 known chigger mite species, Euschoengastia numerosa and Neoschoengastia americana, and 4 undescribed species of Neoschoengastia chiggers attached to individuals of 11 bird species in southeastern Arizona. Groschupf incidentally discovered clusters of the orange-colored chiggers while examining migrant and local birds for Amblyomma cf. triste, a hard tick documented as uncommon and discontinuously widespread in southeastern Arizona, southern New Mexico, West Texas, and northwestern Mexico. All of these ectoparasite collection records are new for these particular bird host species in Arizona, and Savannah Sparrow (Passerculus sandwichensis) is an entirely new host record for A. cf. triste. The effect of these infestations on the birds’ survival and reproductive success is unknown.