The nest and nestlings of Myiobius atricaudus snethlagei (Passeriformes: Onychorhynchidae)

The Black-tailed Flycatcher, Myobius atricaudus, is a Neotropical insectivorous bird with seven recognized subspecies. Information on the breeding of this species is scarce and restricted only for M. a. atricaudus and M. a. ridgwayi. This contribution focuses in one nest of M. a. snethlagei, a subspecies from northeastern Brazil. The nest was observed on 15 February 2017 in the northeastern slope of Araripe Plateau, Ceará State, Brazil. It contained two nestlings devoid of down, with swallow flanges and mouth bright yellow. The nest was a long and closed pensile structure, attached from the tip to a slender branch and suspended 89 cm over a small stream inside the forest. Nest dimensions were: outside height 41 cm, outside diameter 52.5 mm, inside height 62.9 mm, inside diameter 44.6 mm, and circular chamber entrance 43.6 x 31mm. It was mainly composed of long rootlets, strips of dried leaves, tendrils and some fine sticks. The nest was found during the rainy season, but it does not correspond to the breeding season of birds in other localities of northeastern Brazil, where rains occur in other periods. Despite several similarities among the nests of M. a. atricaudus and M. a. snethlagei, entire leaves and spider web were not observed among the materials used to build the nest of M. a. snethlagei, and this might be a useful feature to differentiate the nests of these subspecies. Furthermore, the nest description is consistent with the pattern of architecture known for the members of Family Onychorhynchidae.