Rhodolith distribution, morphology, and cryptofauna have been minimally studied on fringing reefs. We present the first study to examine both rhodolith distribution and associated cryptofauna in a tropical fringing reef, located along the microtidal, wave-dominated north shore of Moorea, French Polynesia. We find higher abundances of larger, rounder, and more branching rhodoliths in locations where longer waves impact the fringing reef. Among 1879 animals extracted and identified from 145 rhodoliths, ophiuroids, polychaetes, decapod crustaceans, and gastropods are most abundant, with a wide range of additional taxa contributing to diversity. Large and branching rhodoliths contain the greatest number and diversity of cryptofaunal organisms and are the preferred habitat of rigid-bodied, non-burrowing forms. Overall, exposure to waves entering the lagoon through passes appears to be a critical determinant of rhodolith abundance, morphotype, and in turn cryptofaunal composition in fringing reef habitats.

A new species of sparid fish, Acanthopagrus oconnorae, is described based on 11 specimens collected in the shallow (0–1 m depth) mangrove‐adjacent sandflats of Thuwal, Saudi Arabia. The new species is distinguished from its congeners by the following combination of characters: second anal‐fin spine 12.8%–16.6% of standard length (SL); 3½ scale rows between the fifth dorsal‐fin spine and lateral line; suborbital width 5.7%–6.7% of SL; eyes positioned at the anterior edge of the head, often forming a weakly convex break in an otherwise gently curved head profile, when viewed laterally; caudal fin light yellow with black posterior margin (approximately half of fin); anal fin dusky grey, with posterior one‐fifth of the fin light yellow; black streaks on inter‐radial membranes of anal fin absent. The most similar species to A. oconnorae is Acanthopagrus vagus, which differs by the presence of a w‐shaped anterior edge of the scaled predorsal area, a more acute snout and black streaks on the inter‐radial membranes of the anal fin. Phylogenetic placement and species delimitation of A. oconnorae are discussed based on COI, CytB and 16S sequences. It is hypothesized that ecology and behaviour explain how this species avoided detection despite its likely occurrence in coastal areas of the Red Sea with historically high fishing pressure.

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In November 2020, we observed several individuals and collected one juvenile of an unidentified anthiadine fish (Serranidae) between depths of 250 and 307 m near vertical walls of rocky reefs in the northern Red Sea. Further morphological and molecular analyses revealed that the collected specimen matches Sacura boulengeri, a species previously reported only from the Gulf of Oman to India.