FAMILY VIREONIDAE 



209 



Description. — Adult (sexes presumably alike), superciliary, spot 

 at lower front of eye, and throat pale lemon yellow; lores blackish; 

 crown light blue; rest of upper surface parrot green, slightly lighter 

 on upper tail coverts; side of face and wing coverts green; primaries 

 and secondaries black, with outer web edged green; tail green; under- 

 tail coverts greenish yellow; rest of undersurface dull green-yellow; 

 edge of wing, underwing coverts, and edge of inner web of primaries 

 and secondaries pale lemon yellow. 



Measurements. — Type (female from Cana, Darien), wing 70.0, tail 

 44.6, culmen from base 18.1, tarsus 22.1 mm. 



Resident. The only specimen known from Panama is a female 

 collected at Cana (900 m), Darien, by E. A. Goldman on June 11, 1912. 

 Nelson described this as the type of a new subspecies, mutabilis, that 

 was said to differ from eximius in having the supraloral part of the 

 superciliary stripe broader, the forecrown greener, auriculars bordered 

 with blue, yellow of throat changing abruptly into and contrasting with 

 yellowish green of breast (however, there is a large patch of feathers 

 missing from this area in the type), green of underparts paler, and 

 undertail coverts brighter yellow. Blake (Check-list Birds World, 

 vol. 14, 1968, p. 109) referred birds from Cordoba and Antioquia, 

 Colombia, to mutabilis, but the series in the Smithsonian from this area 

 is not separable from birds taken elsewhere in Colombia within the 

 range of eximius. These specimens show that none of the characters of 

 mutabilis are constant, the only possible distinguishing feature being 

 the brighter undertail coverts of the type. Without additional speci- 

 mens from Panama, it would be rash to conclude that mutabilis is a 

 valid subspecies. It certainly does not constitute a "connecting link" 

 with V. pulchellus viridiceps as postulated by Hellmayr (Cat. Bds. 

 Americas, pt. 8, 1935, p. 189), and for this reason it seems prudent to 

 maintain eximius as a distinct, monotypic species. 



Ridgely (in. litt.) has seen this species on two occasions in eastern 

 Darien; 2 seen separately on slopes of Cerro Quia (530, 600 m) on 

 July 17, 1975, and 1 seen above Cana (670 m) on March 2, 1981. All 

 3 birds were foraging with mixed flocks in and just below the canopy. 

 Ridgely never saw a bird sing, but believes that a shrike-vireolike song 

 heard repeatedly must have been this species. It was distinctly more 

 single-noted than is typical for pulchellus, e.g., pete-pete-pete. Of in- 

 terest was his failure on either trip to even hear shrike-vireos at low- 

 land locales; they were not present at Cana itself, only above. 



At Santa Fe, western Darien, on March 23 and 31, 1967, Eisenmann 



