The city's first siblings will be leading the parade of costumed summer revelers during this year's Mermaid Parade.

The organizers of the June 21 celebration at Coney Island announced Thursday that Dante and Chiara de Blasio are this year's King Neptune and Queen Mermaid. The teens, who are 16 and 19 respectively, were chosen because of their popularity among the city's youth, according to Coney Island USA founder Dick Zigun, who has been organizing the parade since 1983.

"King Neptune and Queen Mermaid represent the young adults of New York City who are the next generation of visitors to Coney Island," he said in a statement.

Past King Neptunes and Queen Mermaids included Lou Reed, Laurie Anderson, David Byrne, Queen Latifah, Judah Friedlander, Carole Radziwill, Harvey Keitel and Dapne Keitel.