“…This trait distinguishes O. insularis from O. vulgaris sensu stricto and other members of the O. vulgaris complex, such as the geographically co‐occurring O. americanus , both of which are nocturnal in the field (Altman, 1966; Bennice et al, 2021; Kayes, 1973; Lane, 1960; Woods, 1965). Indeed, despite overlapping geographic ranges (Avendaño, Hernández‐Flores, et al, 2020; Avendaño, Roura, et al, 2020; O'Brien, Bennice, & Leite, 2021) and their similar size and appearance, the diurnal behavior observed in this study further reinforces the idea that O. insularis and O. americanus occupy distinct ecological niches: O. insularis is adapted to warmer (23°C–29°C), generally shallower (0.5–40 m) water, and is active mostly during the day (Leite, Haimovici, & Mather, 2009; Leite et al, 2008; Rosas‐Luis et al, 2019; present study), while O. americanus prefers colder (18°C–25°C), usually deeper (up to 200 m) water and is active at night (Amado et al, 2015; Bastos, 2018; Lima et al, 2017). As with Macrotritopus cf.…”