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*WHITE-THROATED SHRIKE-TANAGER  Lanio leucothorax 20–21.5cm.

Rather large arboreal tanager of humid forest, especially in hilly terrain. Pairs

and singles range mainly at mid–upper levels inside forest, usually with diverse

mixed flocks for which the shrike-tanager often acts as a core member and

sentinel. Perches upright and often still for long periods, watching for

invertebrate prey before sallying out to snatch it; at times sounds an alarm call

to distract other birds and pirate prey items. Relatively large size and behavior

distinctive, and male plumage striking, but cf. orioles. Female best told by size,

habits, stout hooked bill, also note tawny rump. Juv. resembles female but

rustier-toned overall, mandible paler, grayish. Comprises 2 groups that may represent species: White-

throated Shrike-Tanager L. [l.] leucothorax of Caribbean slope, in which male has yellow rump and tail

coverts, female has paler tawny rump; and Black-rumped Shrike-Tanager L. [l.] melanopygius of s.

Pacific slope, in which male has black rump and tail coverts, female has concolor back and rump.

SOUNDS: Varied. Common calls a downslurred whistled chew and si’chew, can be repeated steadily or given

in fairly rapid short series; average higher, more piercing in Black-rumped. Also rapid, slightly squeaky

descending twitter run into prolonged series of chu and ch’tu notes may be alarm call; short clucking

chatters may recall Summer Tanager or (in Black-rumped) a thrush clucking, often preceded by si chu or

si chu-chu-chu phrases. Song infrequently given, a prolonged, slightly disjointed medley of squeaks,

whistles, chips, splutters, and short warbled phrases. STATUS: Uncommon on both slopes, to 800m on

Pacific slope, mainly 100–900m on Caribbean slope. (Honduras to w. Panama.)

*GRAY-HEADED TANAGER  Eucometis penicillata 16.5–18cm. Medium-size

tanager of humid lowland forest, adjacent taller second growth. Pairs or small

groups forage mainly at low to mid-levels in understory; often at army ant

swarms, where can be shy and overlooked easily. Nothing really similar in Costa

Rica: note bright yellow underparts, sharply demarcated gray head that often

has bushy crest, habits. Juv. duller overall with olive head; soon attains adult

plumage. SOUNDS: Hard, low clipped tuk; high sharp siip, at times run into

lisping twitters. Song a varied, usually rather fast-paced, rich sharp warble,

which might suggest a euphonia; also a slightly jerky series of high, sharp,

lisping chips. STATUS: Uncommon to fairly common on humid s. Pacific slope, locally to 1600m; more

local on drier n. Pacific slope and in n. Caribbean lowlands. (Mexico to S America.)

MITROSPINGIDS (MITROSPINGIDAE; 1 SPECIES) Small assemblage of

neotropical songbirds, formerly subsumed within tanagers. Ages differ slightly, sexes similar.

DUSKY-FACED TANAGER  Mitrospingus cassinii 18–19cm. Humid lowland

forest understory and edge, adjacent second growth, streamside and marshy

thickets, overgrown plantations. Usually in small noisy groups, often twitching

wings and foraging restlessly in dense shady understory, rummaging in foliage,

visiting fruiting shrubs and sometimes ranging into subcanopy. Tends to be

wary and difficult to see clearly, but locally visits fruit feeders. Nothing similar

in Costa Rica: note habits, voice, staring pale eyes in dark face, bright olive cap.

Juv. duller and messier overall but with same basic pattern as adult, eyes duller.

SOUNDS: Sharp, slightly metallic to rolled chips repeated, chrrit, chrrit chrrit...,

at times with slow spluttering cadence. Dawn song a slightly jerky slow warble of high, vaguely tinny

sharp chips, 3–8 secs, repeated every few secs. STATUS: Uncommon to fairly common on Caribbean slope,

to 600m. (Nicaragua to w. Ecuador.)