The scarlet-backed flowerpecker (Dicaeum cruentatum) is a member of the Dicaeum subfamily of flowerpeckers (Dicaeidae). They are small, sexually dimorphic birds, the males being distinguished by a scarlet cap that extends down the back. The wings and head otherwise are dark navy blue, and the neck and belly are white. The female is a light greyish brown in color with a white belly. It can be identified by a mostly inconspicuous bit of scarlet at the base of the tail.
While widespread in Hong Kong, these birds are rather difficult to spot, being especially small and fast, like other flowerpeckers. They frequent mature forests, primarily feeding on fruits and seeds, but they also frequent more urban settings, such as Kowloon Walled City Park, and have been recorded in Hong Kong visiting Syzygium jambos.