East-central Brazil (southern Piauí to northern Minas Gerais, southern Goiás, Distríto Federal, eastern Mato Grosso do Sul) and east-central Paraguay (Concepción).
 
Population
Estimated population is unknown (2010).
Status LC
Habitat destruction and degradation through agricultural conversion, charcoal production, are the main threats. Habitat may be affected by fire spreading from adjacent grasslands and farms.
For more information see BirdLife International Species Factsheet.
Reiser's Tyrannulet (Phyllomyias reiseri) [XC438775]
by Caio Brito from Lapa Grande State Park, Montes Claros, Minas Gerais, Brazil (song)
Reiser's Tyrannulet (Phyllomyias reiseri) [XC17075]
by Jeremy Minns from Tagatyja-mi, Concepcion, Paraguay (dawn song)
Subspecies
No subspecies.
Genus as presently constituted may be polyphyletic. Anatomical evidence suggests that Planalto Tyrannulet (Phyllomyias fasciatus), Grey-capped Tyrannulet (Phyllomyias griseocapilla) and Sooty-headed Tyrannulet (Phyllomyias griseiceps) may be unrelated to others of genus, some or all of which possibly better placed in resurrected genus Tyranniscus. Appears to form a superspecies with Greenish Tyrannulet (Phyllomyias virescens) and Urich's Tyrannulet (Phyllomyias urichi) and probably closest to Urich's Tyrannulet (Phyllomyias urichi). All were for long considered conspecific, but differences in morphology (plumage pattern, wing and tail proportions), degree of sexual dimorphism, habitat and voice evident. Has been suggested that Sclater's Tyrannulet (Phyllomyias sclateri) also belongs in this group.