Notes On The Nesting Of The Rough-Legged Tyrannulet (Phyllomyias Burmeis-Teri): Phylogenetic Comments And Taxonomic Tracking Of Natural History Data

The Rough-legged Tyrannulet (Phyllomyias burmeisteri) is considered monotypic, yet two populations can be distinguished: the allopatric, apparently larger and longer-tailed Yungas population can be referred to as P. burmeisteri salvadorii, and the Atlantic Forest population as P. b. burmeisteri. Although a nest and egg from the Brazilian Atlantic Forest were assigned to this species, subsequent taxonomic use suggests they may belong to the Greenish Tyrannulet (Phyllomyias virescens). A nest of P. burmeisteri found on 8 September 1995 in the Atlantic Forest of Paraguay was a cup made of twigs, roots and covered in lichen, placed c. 20 m up on a horizontal bough. Another one found on 31 December 2013 in the Yungas of Argentina was a relatively large cup lined and covered with green "old-man's beard" lichens in the upper outer rim, with abundant and relatively large flakes of glaucous foliar lichens on the sides, and placed 7.6 m above the ground on a mossy and licheny horizontal fork in a secondary horizontal branch of Myroxylon peruiferum. Both sexes contributed to nest construction and fed the nestlings, which were partially covered with grayish-white down and had black skin. We recorded an assortment of vocalizations during nesting duties. Our nests resemble that reported by von H. Ihering in 1900, but we cannot rule out whether his description pertains to P. virescens. The use of cup-shaped nests to establish phylogenetic relationships is at present limited, mostly by their simplicity and the lack of detailed descriptions.