The smallest are called guineos ninos or baby bananas. There can be about 4 to 5 inches long, starchier than regular bananas snf even sweeter when almost black.
 
 Nutritional value per 126g or by 110 calories:
Total Fats
0g
Saturated Fat
0g
Trans Fat
0g
Dietary Fiber
4g
Total sugars
21g
Protein
1g