A small, inconspicuous, and easily overlooked sunbird of mountain forests. At a distance, appears fairly uniform in color, but in good light the greenish back contrasts with the gray face, olive throat, pale belly, and reddish tufts on the sides of the body that are sometimes concealed by the wings. Bill is not overly long, but is distinctly curved. Within its range, most likely to be confused with Little Green Sunbird, but Ursula’s Sunbird has a plain face and more decurved, all black bill. Song varies, but always consists of sharp, high-pitched notes that are sometimes delivered as a jumble and sometimes as a single note followed by a descending pattern of quick, high pitched notes: “tsee-TSEE-TSI-tsi-tsi.”