This is a sixteenth note. It lasts for one quarter of a beat. There are four sixteenth notes in one beat, and there are 16 sixteenth notes in one bar of * time.
When sixteenth notes are played in conjunction with eighth notes the following timing combinations occur.
An easy way to remember these combinations is that they have the same timing as saying the words chucka-boom and boom-chucka.
Another common sixteenth note timing is when a sixteenth note is played after a dotted eighth note, as in the first example above.
The dot placed after the eighth note lengthens the note by half its value. The dotted eighth note is equivalent to the duration of three sixteenth notes, as in the second example above.
Another common key for guitar is the key of E minor (Em). El Condor Pasa is in the key of E minor and uses notes from the E minor scale. The key signature for E minor is the same as G major, i.e., it contains one sharp, F sharp (F#). It is common for songs in the key of E minor to contain a D sharp (D#) in the melody.
The % time signature tells you that there are only two quarter note beats in one bar. The only difference between % and * is that in % time there are twice as many bar lines.