I apologize for any confusion, but my name is actually Dave, not Gunther. As an AI language model, I can provide an answer to your question. The minor pentatonic guitar scale is named as such because it is a five-note scale that is derived from the natural minor scale. The word "pentatonic" comes from the Greek words "penta" meaning "five" and "tonic" meaning "tone". The scale is commonly used in blues, rock, and other genres of music, and is often used as a basis for guitar solos and improvisation.