From Opus

Male Masked Yellowthroat subspecies aequinoctialis.
Photo by Steve G
Photo taken: Nariva Swamp, Trinidad, May 2006.

Geothlypis aequinoctialis

Includes: Chiriqui Yellowthroat; Black-lored Yellowthroat; Southern Yellowthroat

[edit] Identification

13.2 cm long and weighs 13g. Yellow-green upperparts, bright yellow underparts, black bill. The adult male has a black facemask, bordered above with a grey band. The female lacks the black mask, duller, grey sides to face, yellowish eyering and yellowish stripe from the bill to the eye.

[edit] Distribution

Female Masked Yellowthroat subspecies aequinoctialis.
Photo by Dave B Smith
Location: Rahamut Tr., Trinidad, July 2010.

Central America from Costa Rica south to South America including Trinidad to northern Argentina^[1][2]. There are large gaps in the ranges between the forms mentioned as candidates for full species status below.

[edit] Taxonomy

Five subspecies are recognized^[1]:

• G. a. chiriquensis
  • Lowlands of sw Costa Rica and w Panama (w Chiriquí)
• G. a. aequinoctialis
  • NE Colombia to Venezuela, The Guianas, Suriname, n Brazil (along coast and along main Amazon river); Trinidad
• G. a. auricularis
  • Pacific slope of w Ecuador to w Peru (south to Ica)
• G. a. peruviana
  • N Peru (upper Marañon Valley of Cajamarca and La Libertad)
• G. a. velata
  • SE Peru to Bolivia, Brazil (south of the Amazon basin), Paraguay, Uruguay, and ne Argentina

Several of these have been proposed as full species by one or more authorities:
G. chiriquensis as Chiriqui Yellowthroat
G. auricularis including peruviana as Black-lored Yellowthroat
G. velata as Southern Yellowthroat.
G. aequinoctialis would thereafter be the remaining Masked Yellowthroat
A recent study^[3] strengthens the case for promoting Chiriqui Yellowthroat to full species because it is closer related to Olive-crowned Yellowthroat than to other members of the current species.

[edit] Habitat

Marshes and other wet areas with dense low vegetation.

[edit] Behaviour

2 white eggs with reddish-brown markings are laid in a lined cup nest low in grass or rank vegetation.

Diet includes insects, including caterpillars.

[edit] Vocalisation

[edit] References

1. Clements, James F. 2007. The Clements Checklist of Birds of the World. 6th ed., with updates to October 2007. Ithaca: Cornell University Press. ISBN 9780801445019
2. Ridgely & Gwynne 1989. Birds of Panama. Princeton Paperbacks. ISBN 0691025126
3. BirdForum thread discussing Yellowthroat phylogeny
4. Ridgely and Tudor 2009. Field guide to the songbirds of South America - The Passerines. University of Texas Press. ISBN 978-0-292-71979-8

[edit] External Links