SUMMARY
The confusing taxonomic history of Rough-legged Tyrannulet (Phyllomyias burmeisteri) casts doubt on whether a nest and egg from Brazilian Atlantic Forest might instead belong to the Greenish Tyrannulet (Phyllomyias virescens). A nest of P. burmeisteri placed 7.6 m.-up on a horizontal fork in a secondary horizontal branch of Myroxylon peruiferum in late December 2013 in the Yungas of Argentina was a relatively large cup lined and covered with green "old-man's beard" in the upper outer rim, with abundant relatively large flakes of foliar lichens on the sides. Another nest found in early 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. These nests resembled that reported by Ihering. Usage of cup-shaped nests to establish phylogenetic relationships is limited by their simplicity and the lack of detailed descriptions.