Elasmobranch reproductive behaviour remains understudied, particularly for batoids (rays). Most of the information available originates from opportunistic observations of mating scars in the wild and/or from individuals held in captivity. Here we describe the first complete mating sequence of the marbled ray Taeniurops meyeni) in the wild. The event was filmed at Isla del Coco National Park in Costa Rica, in the Tropical Eastern Pacific. The complete sequence lasted approximately 3 hrs and is defined by the following behaviours: (1) close following or chasing: a group of males swim in a close formation chasing an individual female; (2) pre-copulatory biting: oral grasping of the female’s posterior pectoral fin by the males, with anterior bending of one clasper and rotation of the pelvic region towards the female’s cloaca; (3) copulation/ insertion of the male’s clasper followed by ‘ventral to ventral’ position and energetic thrusting of the male’s pelvic region; (4) post-copulatory behaviour: the male removes its clasper from the female’s cloaca while releasing her posterior pectoral fin and (5) separation: the male sets the female free and separates himself from the group. The mating behaviour described here shares some similarities with the few other studies of batoids in the wild and highlights the need to further understand their mating system to guide conservation plans for this vulnerable species.