FAMILY TI IRAUPIDAE 



383 



the more specialized groups, and points to the need for much greater 

 study of the entire New World nine-primaried assemblage before it can 

 be satisfactorily determined whether some of the species now con- 

 sidered tanagers are not in fact more closely allied to parulids or em- 

 berizids. Many of the Panamanian species are little known and ad- 

 ditional information on their life histories may be useful taxonomically. 

 For example, members of the distinctly marked genus Euphonia and 

 the related Chlorophonia feed primarily on mistletoe berries, for which 

 their digestive tract is specially adapted, and are the only tanagers 

 known to build domed nests with an entrance on the side; most other 

 tanagers build a cup-shaped nest. The Swallow-Tanager, which nests 

 in holes, is often placed in a separate family Tersinidae, but Sibley 

 (Bull. Brit. Orn. Club, 1973, pp. 75-79) argues convincingly for 

 putting it in the Thraupidae near Tangara and Thranpis. 



Three North American tanagers of the genus Piranga are found as 

 migrants and winter visitors. Most of the resident tanagers are indif- 

 ferent singers, the exceptions being in the genera Piranga, Ilabia, and 

 Rhodinocichla. Many tanagers are part of the mixed species flocks that 

 roam through forest and second growth, feeding on fruit and insects. 



KEY TO SPECIES OF THRAUPIDAE: TANAGERS 



1. Undersurface primarily rosy or red 2 



Undersurface not primarily red 10 



2. Wings black or blackish 3 



Upper surface, including wings, close to color of undersurface 7 



3. Wings with two white bars 4 



Wings unmarked 5 



4. Undersurface orangish red, large, 165 mm or more. 



male Flame-colored Tanager, Piranga bidentata citrea. p. 455 

 Undersurface bright red, small, 140 mm or less. 



male White-winged Tanager, Piranga leucoptera latifasciata. p. 457 



5. Undersurface rosy, back blackish. 



male Rosy Thrush-Tanager, Rhodinocichla rosea eximia. p. 483 

 Undersurface scarlet or darker, back red 6 



6. Upper surface and undersurface scarlet. 



alternate plumage male Scarlet Tanager, Piranga olivacea. p. 453 

 Throat darker than rest of undersurface. 



Crimson-backed Tanager, Ramphocelus dimidiatus. p. 440 



7. Crown and upper surface uniform 8 



Crown dark, with central red stripe 9 



8. Entire body orangish red. 



male Hepatic Tanager, Piranga flava testa cea. p. 451 



Entire body pinkish red. 



male Summer Tanager, Piranga rubra rubra, p. 452 



