Here is information about the kumquat.
Common names: Kumquat, cumquats
The kumquats or cumquats are a family of small fruit-bearing trees in the flowering plant family Rutaceae, in the genus Fortunella which is often included in the genus Citrus. The edible fruit closely resembles that of the orange (Citrus sinensis), but is smaller and is often oval.
A few salted kumquats with a few teaspoons of brine/juice may be mixed with hot water to make a remedy for sore throats.