Piquin (or Pequin) pepper originates in the Mexican state of Tabasco, where it's widely used to make salsa or complimentary to many dishes. It's also known as chile pequín, chile petín and Chiltepe. 

Pequin has a compact habit, growing typically 1 or two feet tall, with bright green, ovate leaves and small berries up to one inch in length. Like most chilies, the berries start out green, ripening to brilliant red at maturity. Pequin peppers are very hot, often 5–8 times hotter than jalapeños on the Scoville scale (30,000 to 60,000 Units). Flavor is described as citrusy, smoky (if dried with wood smoke), and nutty.