Northern Bentbill (Oncostoma cinereigulare) [XC773027]
by Paul Driver from La Esmeralda, Santa Mar\u00eda Chimalapa, Oaxaca, Mexico (song)
Northern Bentbill (Oncostoma cinereigulare) [XC622]
by David Bradley from Santa Rosa National Park, Costa Rica (song)
Subspecies
Has been suggested by some authors that genus be joined with closely affiliated Hemitriccus or Lophotriccus. However, bill morphology and peculiar voice viewed by others as sufficiently distinct to support retention of separate genus. Forms a superspecies with Southern Bentbill (Oncostoma olivaceum), and sometimes considered conspecific. Distribution somewhat uncertain.