Masked Gnatcatcher

polioptila dumicola

Polioptilidae · Gnatcatchers

Disc 2 · 2001 listed
Disc 3 · 2006 listed
Disc 1 · 2011 listed

The account

Description

12.5 cm. Male bluish gray above with a black mask which is bordered underneath by a white stripe. Black wings with white-edged primaries and secondaries. Black tail with white outer feathers. Underside gray.

The female is similar to the male, but instead of the mask has a thin black eye stripe. Cheeks whitish.

Male Disc 3 · 2006
Female Disc 3 · 2006

Each plate is labelled with the disc's own caption.

Where it was recorded

The discs' own checklists select Masked Gnatcatcher at 1 locality.

Historical checklist localities on the disc's own area map — the red dots the original program drew, placed by its recovered projection. Not a range map: it shows the places whose checklists record the bird, nothing more.

Serra da Cantareira SRSB

How the map was made

The original program computed each red dot at display time from the locality's coordinates, using its map library and one of five base maps drawn for the screen widths of the day. That library's projection — an oblique rotation of the sphere about the map's own centre, 23.7°S 47.4°W — was read from the program and checked against the graticule the same program drew into the base maps: it reproduces every grid intersection to within about a pixel. The dots here use that projection on the 1280-pixel base map, with the coordinates the discs record. Nothing was placed by hand, no modern map data was used, and a place whose coordinate is incomplete, out of range or beyond the map's edge is listed rather than guessed.

The discs carried location maps only; none shows a distribution or range.

Voice

Song variable (Vocalization # 1-5). A common note is a 'swee swee" interwoven into the song. Various short notes are used in the song: 'zitu zitu zitu zi zi zi zi, zwi zwi zwi zizizizizi' etc.

Behavior

Forages in the crowns of trees and shrubs.

Habitat and status

Uncommon, in dry forest and open tree savanna, cerradao, cerrado.

Distribution

Mostly extralimital inland. Absent from the coastal regions, but expected to occur at times closer to the coast. To 800 meters

Decoded from the disc's own bytes. Each part is shown under the heading the disc files it under, and the wording, spelling and punctuation are the author's.

Vocalizations

Song, Pocone, Transpantaneira, MG, LSD 109935, recorded by M. Medler.
Song, calls, October 24, 1974, Bage, Rio Grande do Sul, in background Aramides ypecaha. Recorded by W. Belton.
Song, Uruguaiana, Arroio Quarai Chico, RG, LSN 20122, recorded by W. Belton, remarks by W. Belton
Song, Arroio Quarai Chico, Uruguaiana, RG, LNS20124, recorded by W. Belton, remarks by W. Belton.
Song, Arroio Quarai Chico, Uruguaiana, RG, LNS 20125, recorded by W. Belton. Remarks by W. Belton. With Tapera naevia, long song, and Aramus guarauna.

Recording files on the disc

2091.mp3 Song, Pocone, Transpantaneira, MG, LSD 109935, recorded by M. Medler.
7977.mp3 Song, calls, October 24, 1974, Bage, Rio Grande do Sul, in background Aramides ypecaha. Recorded by W. Belton.
3303.mp3 Song, Uruguaiana, Arroio Quarai Chico, RG, LSN 20122, recorded by W. Belton, remarks by W. Belton
8657.mp3 Song, Arroio Quarai Chico, Uruguaiana, RG, LNS20124, recorded by W. Belton, remarks by W. Belton.
3026.mp3 Song, Arroio Quarai Chico, Uruguaiana, RG, LNS 20125, recorded by W. Belton. Remarks by W. Belton. With Tapera naevia, long song, and Aramus guarauna.

Across the three discs

The work was published on three discs — Disc 2 in 2001, Disc 3 in 2006 and Disc 1 in 2011. Where they differ, that is a difference between historical releases, and it is never merged away. The 2011 disc is not treated as correcting the earlier ones.

Which discs list this bird

Disc 2 · 2001 — in this disc's bird list
Disc 3 · 2006 — in this disc's bird list
Disc 1 · 2011 — in this disc's bird list

How that was established

Disc 2 · 2001: aux_nonzero;local_checklist_byte45_flag_1
Disc 3 · 2006: aux_nonzero;local_checklist_byte45_flag_1
Disc 1 · 2011: aux_nonzero;local_checklist_byte45_flag_1

The disc's own record fields that place the bird on its list: a non-empty entry in the species table, and the byte that marks it as selected on a local checklist.

The account in the Disc 1 · 2011 revision

The 2011 Disc 1 revision carries this account text unchanged from the Disc 3 release.

The work's own taxonomy

The discs carried three parallel name schemes. All three are shown as recovered; none is a modern taxonomy and none has been updated.

Scheme	Scientific name	English name	Family
WORLD	polioptila dumicola	Masked Gnatcatcher	Polioptilidae
CLEMENTS	polioptila dumicola	Masked Gnatcatcher	Polioptilidae
AOU_HM	polioptila dumicola	Masked Gnatcatcher	Polioptilidae

Source details

Identifier on this site: seb_species_0335
Account identifier: seb_account_0335
Account number on the disc: 335
Source edition: CD03 / 2006 package
Original taxonomy scheme: WORLD
Structure status: heuristic; decoded_account_text and segment JSON remain authoritative