Northern Beardless-Tyrannulet © allaboutbirds.org

Forms a superspecies with Southern Beardless-Tyrannulet (Camptostoma obsoletum). The two overlap slightly without intergrading in west-central Costa Rica. Birds from southern USA (Arizona) and north-western Mexico, supposedly longer-billed, more olive above and more yellow below, described as subspecies ridgwayi. Birds from Cozumel I, named as thyellophilum on basis of minute differences in mean culmen length in a small sample. However, both considered indistinguishable from other populations.


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BirdLife International For more information about the Northern Beardless-Tyrannulet see... BirdLife International Species Factsheet. Articles about the Northern Beardless-Tyrannulet If you would like to read any articles about the Northern Beardless-Tyrannulet... Show Articles (0) No Pictures of Northern Beardless-Tyrannulet If Birdpedia has no pictures of Northern Beardless-Tyrannulet or you would like to see more, then try the following...       From BING (6) No Videos of Northern Beardless-Tyrannulet If Birdpedia has no videos of Northern Beardless-Tyrannulet or you would like to see more, then try the following..       From BING (0) Where can I observe this species? Select an area (or leave blank) to see locations where this species has been recorded. Area   COSTARICA COCOS   All    Optional: Complete the following if you wish to restrict the reserve to within a given distance of a location. Please enter the Latitude and Longitiude of a given location together with the maximum distance (km) to display a list of reserves within that distance. You must enter a Latitude, a Longitude and a distance greater than 0.   Latitude: (Decimal degrees takes precedence) Deg Min Sec     Decimal degrees (Include compass setting or value)          N S or   GPS help Longitude: (Decimal degrees takes precedence) Deg Min Sec     Decimal degrees (Include compass setting or value)          E W or   Find GPS using Google Maps Distance Bearing     N NE E SE S SW W NW Get Sample GPS readings On What Field Trips was this species observed? Select an area (or leave blank), and a date range, to see field trips on which this species has been recorded. Area   COSTARICA COCOS   All    From To     Optional: Complete the following if you wish to restrict the reserve to within a given distance of a location. Please enter the Latitude and Longitiude of a given location together with the maximum distance (km) to display a list of reserves within that distance. You must enter a Latitude, a Longitude and a distance greater than 0.   Latitude: (Decimal degrees takes precedence) Deg Min Sec     Decimal degrees (Include compass setting or value)          N S or   GPS help Longitude: (Decimal degrees takes precedence) Deg Min Sec     Decimal degrees (Include compass setting or value)          E W or Distance Bearing     N NE E SE S SW W NW Get Sample GPS readings Latest Sightings for Northern Beardless-Tyrannulet Select the Area to restrict the Sightings. Area   COSTARICA COCOS   All