The Adufe is a square-shaped membranophone, introduced to Portugal by the Arabs in the 8th and 9th centuries. It has a square wooden structure and is covered on both sides with tanned goatskin. Traditionally one of the faces is that of a male animal, the other that of a female animal (some say it sounds better that way !). In the corners there are decorations with colored ribbons.

It is played in a vertical position and struck with the fingers and hands. Inside there are grains, seeds or small stones that make  a rattling noise when shaking the Adufe. It is an instrument usually played by women (“adufeiras”) and has a strong presence in the interior of central Portugal.

https://en.wikipedia.org/wiki/Adufe

I used the old and very rough wooden structure of a small-sized adufe as a frame for a small painting (oil on plywood), as a memory of its origin.