From Wikipedia
An idiochord (Latin: idio – "self", chord – "string", also known as a drum zither) is a musical instrument in which the "string" of the instrument is made from the same material as its resonating body. Such instruments may be found in the Indian Ocean region, disparate regions of Africa and its diaspora, and parts of Europe and North America.
Bamboo is often a popular material for idiochords: a tube of bamboo may be slit to loosen portions of the husk at the middle, leaving them attached at the ends, and these "strings" may be raised up by inserting sticks to serve as bridges. Such bamboo idiochords include the valiha of Madagascar, the kulibit in the Philippines and Indonesia, and the karaniing of the Mon-Khmer "Orang Asli" tribal peoples of Malaysia. A massive one-string bamboo idiochord, the benta, is native to Jamaica and played with a slide, much like a diddly-bow.