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ANTVIREOS (GENUS DYSITHAMNUS) (3 species). Medium-size, rather chunky arboreal

antbirds with fairly stout bills (recalling vireos). Usually in pairs, often with mixed flocks.

PLAIN ANTVIREO  Dysithamnus mentalis 11–12cm. Humid foothill forest,

arboreal. Often in pairs, foraging methodically at low to mid-levels in shady

understory; joins mixed feeding flocks. Distinctive, with heavy bill, shortish

tail, narrow pale wingbars; note dark cheeks of male, rusty cap and white

eyering of female; cf. Tawny-crowned Greenlet (p. 368), sometimes in same

flocks. Streak-crowned and Spot-crowned Antvireos occur in lowlands, have

pale eyes, streaked chest. SOUNDS: Song an accelerating, laughing, and overall

descending series of (usually 14–28) hollow, slightly nasal whistles, hyu-hyu-

hyu-hyuhyu..., 2–3 secs; recalls Barred Antshrike but higher, more laughing,

lacks final snarl. Calls include a low nasal nyeu-nyeut; and nasal barking kah, often repeated fairly steadily

(suggests quiet Barred Forest Falcon). STATUS: Fairly common to uncommon on both slopes, mainly

700–1500m, rarely lower and locally up to 2500m. (Mexico to S America.)

STREAK-CROWNED ANTVIREO  Dysithamnus striaticeps 10.5–11.5cm.

Humid lowland and foothill forest, adjacent taller second growth; arboreal.

Often in pairs, foraging methodically at low to mid-levels in shady understory;

joins mixed feeding flocks. Told from slightly larger Spot-crowned Antvireo

(limited overlap) by voice, stronger dusky streaking on breast, crown pattern.

SOUNDS: Song a slightly overslurred series of (usually 12–21) slightly whining

nasal whistles accelerating strongly at the end, whi hiu-hiu..., 2.5–3.5 secs. Calls

include a mellow, descending whistled wheu heu and heu. STATUS:  Fairly

common on n. Caribbean slope, to 800m, less numerous in s. Caribbean

lowlands around Limón. (Honduras to Costa Rica.)

SPOT-CROWNED ANTVIREO  Dysithamnus puncticeps 11–12cm. Humid

lowland forest and adjacent taller second growth; arboreal. Often in pairs,

foraging methodically at low to mid-levels in shady understory; joins mixed

feeding flocks. Told from slightly smaller Streak-crowned Antvireo (limited

overlap) by voice, weaker dusky streaking on breast, crown pattern.

SOUNDS: Song a fairly rapid, slightly overslurred, laughing series of (usually

21–34) high piping whistles accelerating slightly at the end, whii pii-pii...,

2.5–3.5 secs; distinctly higher and faster-paced than Streak-crowned Antvireo

song. Calls include quiet, mellow piping notes, soft twittering trills, and a lower

frog-like chirrrr. STATUS: Fairly common on s. Caribbean slope near Panama border, to 800m; in smaller

numbers n. to vicinity of Limón. (Costa Rica to w. Ecuador.)

RUFOUS-RUMPED ANTWREN  Euchrepomis callinota 11–12cm. Handsome,

arboreal, very small and rather warbler-like antwren of humid foothill forest

and edge. Singles and pairs forage actively at mid–upper levels, mainly on

smaller twigs and in foliage, at times hanging upside down; does not hover or

sally as do many warblers and flycatchers. Often with mixed flocks including

tanagers, ovenbirds, warblers. Distinctive, but rusty rump often covered by

wings. Note small size, habits, pale lemon belly contrasting with ashy-gray

breast, distinct lemon to buff wingbars. SOUNDS: Inconspicuous, easily missed.

Song an overslurred, accelerating, chippering trill of high thin notes, tsi-si-si...,

1–2 secs; recalls a warbler. Calls include a high lisping siik and short high twitters. STATUS: Uncommon

on Caribbean slope, mainly 700–1200m. (Costa Rica to S America.)