Frontier Airlines has unveiled its newest aircraft, an Airbus A321neo featuring Bori the Coquí Llanero on its tail, during a celebration at Luis Muñoz Marin International Airport in San Juan, Puerto Rico. Bori the Coquí Llanero pays tribute to Puerto Rico, which is Frontier’s largest Caribbean destination. The airline serves Puerto Rico from San Juan, Aguadilla and Ponce and has been significantly expanding its operations across the island. Frontier has announced a major increase in service over the past several months, growing the total number of routes it operates from Puerto Rico from 11 to 20.

Every Frontier aircraft features an animal on its tail with a special name and backstory. Last year, the airline conducted a Tropical Tails contest, which featured endangered species from six different tropical destinations, one of which would be deemed the winner and featured on a future aircraft. The Puerto Rican lowland coquí received the top vote.

Consumers were then invited to vote on a name for the coquí llanero via social media. ‘Bori’ was the resulting winner and is short for Boricua, which is derived from “Borikén” (the Taino Indian name for the island) and used to describe a person from Puerto Rico by birth or descent.

The Puerto Rican lowland coquí is one of the smallest tree frogs in the world. Mature llaneros are no wider than a dime and generally yellowish in color. Their tiny stature squeezes their vocal range into the highest pitch of almost any frog – just barely audible to human ears, making the sound they are so famously known for and named after — “Ko-Kee.” The coquí llanero is listed as endangered under the U.S. Endangered Species Act.