First record of Boulenger's anthias Sacura boulengeri (Heemstra 1973) in the Red Sea.

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.

Acanthopagrus oconnorae, a new species of seabream (Sparidae) from the Red Sea.

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.

The Grumpy dwarfgoby, a new species of Sueviota (Teleostei, Gobiidae) from the Red Sea.

A new gobiid species is described from ten specimens, 9.2 - 16.7 mm SL, collected from the Saudi Arabian Red Sea. The new species is most similar to Sueviotapyrios from the Gulf of Aqaba in the northern Red Sea. It differs from S.pyrios by having no large red spots on the dorsal and caudal fin elements, no elongate spines in the first dorsal fin, a shorter pelvic fin that does not reach the anus, branched pectoral fin rays, and a projecting lower jaw. The new species is further distinguished from all its congeners by a complete lack of cephalic sensory canals and pores. Specimens were found in small caves and overhangs at depths between 10 and 53 meters.

Morphological and ecological trait diversity reveal sensitivity of herbivorous fish assemblages to coral reef benthic conditions.

Herbivorous fishes play a critical role in the maintenance of coral reefs through grazing and cropping of various benthic algae types. Herbivorous fish assemblages are sensitive to changes in the reef environment and are often targeted by local fisheries. This can lead to a decline in ecosystem functions if key groups are reduced. The present study investigates the morphological and ecological trait diversity of herbivorous reef fish assemblages in habitats differing in relative benthic coverage: i) coral-dominated, ii) algae-dominated, and iii) an intermediate habitat. Trait diversity for conspicuous herbivorous fishes was measured using three trait diversity indices: trait richness, trait divergence, and trait evenness. These indices were derived from in situ community surveys and feeding observations, morphological assessment of feeding mechanics from locally collected specimens, and ecological information obtained from published data. Trait diversity, reflected in higher trait evenness and lower trait richness, was lower within algae-dominated habitats than coral-dominated habitats, suggesting that algae-dominated habitats may be compromised by the lack of essential functions provided by key species. These groups reduce algal biomass and may help facilitate the survival and growth of corals, which in turn can increase coral cover. Algae-habitats were dominated with species known to consume macroalgae (rabbitfish and surgeonfish), appearing to provide essential feeding and habitat resources. These species include browsers and croppers that are fundamental in reducing algal biomass and may help facilitate the survival and growth of corals, which in turn can promote reef health. However, this habitat lacked parrotfishes known to remove turf algae and sediments, an essential function for clearing benthic space for coral settlement and other key benthic invertebrates. This study identified several species with overlapping functional roles in the coral-dominated and intermediate habitats. Still, species that were not redundant showed high trait complementarity, suggesting that their removal may result in the loss of unique functions. Importantly, we show that algae-dominated habitats supported high numbers of juvenile fishes especially in species targeted by local artisanal fishers. We also showed that the loss of trait diversity is greater than the loss of species diversity through the comparison of taxonomic and trait ß-diversity, further emphasizing the importance of trait diversity analysis in understanding ecosystem health and maintenance.