FAMILY TIIRAUPIDAE 



MITROSPINGUS CASSINII (Lawrence): Dusky-faced Tanager, 

 Frutero Carisucio 



Medium size; upper surface very dark gray; with dark yellow tri- 

 angular patch on crown; throat gray, rest of undersurface greenish 

 yellow. 



Description. — Length 155-187. Adult (sexes alike), lores, broad 

 areas around eye, and side of head black; triangular patch on crown 

 dark yellow; rest of upper surface dark gray, sometimes tinged green- 

 ish; wings and tail blackish brown; chin black, becoming gray on 

 throat; undersurface dark yellowish green, lightest on breast; under- 

 wing coverts gray. 



The Dusky- faced Tanager inhabits humid lowland forest and wood- 

 land, where it dwells in thickets, often along streams and borders. This 

 is a shy species that usually twitches its wings and jerks its tail ner- 

 vously whenever it emerges briefly from the undergrowth. It is almost 

 always encountered in rapidly moving, noisy groups of 4 to 12 indi- 

 viduals; they do not often mix with other species, but E. A. Goldman 

 sometimes noted them with Chlorothraupis carmioli and several species 

 of antbirds in the vicinity of traveling ants. Their diet is a mixture of 

 animal and vegetable matter; of the stomachs of 2 taken by Goldman 

 at Cana, Darien, one contained fragments of a scarabaeid 12%, cater- 

 pillar 3%, 4 seeds of Panicum sp. 10%, 13 seeds of Rutaceae (Xan- 

 thoxylum?) 50%, 130 seeds of Miconia sp. 25%, and the other held 1 

 Lachnopus sp. 12%, a carabid 15%, a cerambycid 8%, another beetle 

 5%, a green caterpillar 10%, 3 or more spiders 15%, 9 carunculate 

 seeds 30%, 5 seeds of Solanum sp. 5%. Skutch (Publ. Nutt. Orn. 

 Club, no. 10, 1972, p. 205) found that in Costa Rica it eats insects and 

 a variety of berries, especially those of Melastomaceae, Rubiaceae, and 

 Solanaceae, seeds of the scandent grass Lasiacis, and the small, hard 

 seeds of the tree Alchornea costaricensis. Four collected on Cerro 

 Pirre, Darien, by Burton (Bull. Brit. Orn. Club, 1975, p. 86) weighed 

 from 32 to 39 g. 



Besides various metallic call notes, I once heard a song from this 

 species; in the early morning of February 27, 1961, at the Peluca 

 Hydrographic Station, Panama, one perched on a balsa tree beside the 

 trail, on the very top twig, and sang seety, seety, seety, seety, seety. 



The Dusky- faced Tanager is divided into 2 very poorly differen- 

 tiated races. The nominate form is found from Veraguas east to 

 western Colombia and western Ecuador; in Panama it occurs mainly 

 on the Caribbean slope. The other race, costaricensis, is found in the 



