Batara masqué Xenornis setifrons

This antshrike is distinctive within its small range in eastern Panama and extreme northwest Colombia. Male is dark gray below and brown above with bold buffy spotting on wing coverts with a streaked back and crown. Female is similar, but brown below. Occurs in lowlands and foothills, where pairs skulk around in the understory of humid forest, often following a mixed-species flock. Listen for a rising series of piercing whistles.