Large-headed Flatbill

ramphotrigon megacephala

Tyrannidae,Elaeninae · Tyrannulets

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

The account

Description

13 cm. Dark olive-brown above with a yellow eye ring and supraloral stripe. Wings dark grayish-brown with two buff wingbars and yellow margins to the flight feathers. Throat light yellow. Breast and belly olive-gray, indistinctly streaked darker. Lower belly pale yellow-green. Tail dark grayish-brown.

The disc records this picture against the bird without a caption. Disc 3 · 2006

Where it was recorded

The discs' own checklists select Large-headed Flatbill at 8 localities.

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.

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

Calls are distinctive, consisting of repetitions of low whistles like 'wue.....wue......wue......', 'ju....ju....ju....', 'wiu....wiu....wiu.....', 'due-do......due-do.....due-do.....' etc.

Behavior

Forages from eye level to 5 meters within lower growth of bamboo thickets. Performs upward strikes from a perch within the thicket.

Breeding

Nest found by T. Schulenberg was on the bottom of a 10 cm deep cavity in a broken-off palm stump in the understory of forest near a bamboo thicket (Tambopata Reserve, Peru, ¹¹¹).

Habitat and status

In southeast Brazil the occurrence of this species is associated with dense and extensive bamboo thickets in primary and secondary humid upland forest. Not uncommon but local.

Distribution

Throughout. Serra dos Orgãos, Serra Mantiqueira, Serra do Mar, Fazenda Intervales. Usually at higher elevations. Most common 600-1400 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

Call. Fazenda Intervales, 11/30/97. Misty morning, 22°C. Bamboo forest.
Calls. Fazenda Intervales, 11/30/97. Misty morning, 22°C. Bamboo forest.
Call. Fazenda Intervales, 11/30/97. Misty morning, 22°C. Bamboo forest.
Call. 10/22/99, Serra da Mantiqueira, near Hotel do Ype. Clear, 25°C. Bamboo forest. With Hylophilus poicilotis, Dysithamnus mentalis, Chamaeza meruloides, Basileuterus culicivorus, Trogon viridis.
Call. 10/22/99, Serra da Mantiqueira, near Hotel do Ype. Clear, 25°C. Bamboo forest. With Saltator similis, Basileuterus culicivorus, Myiornis auricularis, Hylophilus poicilotis, Columba plumbea.
Call. 10/22/99, Serra da Mantiqueira, near Hotel do Ype. Clear, 25°C. Bamboo forest. With Columba plumbea, Basileuterus culicivorus.

Recording files on the disc

6393.mp3 Call. Fazenda Intervales, 11/30/97. Misty morning, 22°C. Bamboo forest.
12903.mp3 Calls. Fazenda Intervales, 11/30/97. Misty morning, 22°C. Bamboo forest.
1804.mp3 Call. Fazenda Intervales, 11/30/97. Misty morning, 22°C. Bamboo forest.
14333.wav Call. 10/22/99, Serra da Mantiqueira, near Hotel do Ype. Clear, 25°C. Bamboo forest. With Hylophilus poicilotis, Dysithamnus mentalis, Chamaeza meruloides, Basileuterus culicivorus, Trogon viridis.
3612.wav Call. 10/22/99, Serra da Mantiqueira, near Hotel do Ype. Clear, 25°C. Bamboo forest. With Saltator similis, Basileuterus culicivorus, Myiornis auricularis, Hylophilus poicilotis, Columba plumbea.
1500.wav Call. 10/22/99, Serra da Mantiqueira, near Hotel do Ype. Clear, 25°C. Bamboo forest. With Columba plumbea, Basileuterus culicivorus.

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	ramphotrigon megacephala	Large-headed Flatbill	Tyrannidae,Elaeninae
CLEMENTS	ramphotrigon megacephala	Large-headed Flatbill	Tyrannidae,Elaeninae
AOU_HM	ramphotrigon megacephala	Large-headed Flatbill	Tyrannidae,Elaeninae

Open questions about this bird

Recovered evidence that has not been settled. It is published because leaving it out would misrepresent what the discs contain.

Review notes

review_0009

Recovered review record — open: Moved one terminal visual segment from account 238 to account 237.

Evidence: 11179 is an exact image filename match and precedes Yellow-olive Flycatcher's '14 CM' description. · Recommended: Confirm visually against the original program or field notes when available; retain correction unless contradicted.

Review v1.1 decision — accepted_provisionally

Reviewer: ChatGPT structural audit

Notes: The correction is strongly supported by account grammar, checklist order, species-name evidence, and media-segment placement. Retain in the working dataset; optional confirmation against the original program or field notes remains.

Source details

Identifier on this site: seb_species_0237
Account identifier: seb_account_0237
Account number on the disc: 237
Source edition: CD03 / 2006 package
Original taxonomy scheme: WORLD
Species boundary note: Boundary audited with account 238; one segment reassigned.
Account boundary note: Boundary audited with account 238; one segment reassigned.
Structure status: heuristic; decoded_account_text and segment JSON remain authoritative