there are 1000's of martial art styles
tkd has over 75, there is over 300 hundred kung fu, japanese jujutsu has over 500, karate i'm not actually sure there are 8 styles recognized by WUKO but then there are sub-systems of those 8. if i had to guess i would say about 40 to 50
edit:> pugpaws perhaps i mis-quoted something about tkd, i then, i may have mixed it up the numbers with kung fu. i'm getting old and senile perhaps