<p>Long-term biodiversity exploration and monitoring are essential for understanding temporal and spatial patterns of diversity, as well as assessing the effectiveness of current conservation efforts. Despite increased research in the western Indo-Pacific, recent ichthyological studies continue to uncover a high frequency of new species discoveries and recent findings. In this study, we examine the presence, morphology, scale, and otolith shape variations, osteology, distribution, and molecular phylogenetic relationships of <i>Epinephelus malabaricus</i>, known as the Malabar grouper, from the northwestern of the Oman Sea. The scales were cycloid, ranging from oval/ovoid to oval/true oval and oval/reversed ovoid in different regions of the body, with a fluted rostral margin. The lateral-line scales featured a wide, elongated canal that widened in the anterior region and bifurcated at the end. The otoliths were oval-oblong, with a sinuate/irregular dorsal margin, sinuate inferior edge, and an indented, irregular rear edge. The sulcus groove was medium in size and heterosulcoid, with an ostial opening. The ostium was funnel-shaped, while the cauda was tubular, strongly curved, and ended near the ventral margin. The colliculum was heteromorph, characterized by a well-developed ridge-like crista superior and a generally underdeveloped crista inferior. The spinal column comprised 10 precaudal and 14 caudal vertebrae, totaling 24 vertebrae. Mitochondrial COI-based DNA barcoding sequences demonstrated that some species of the genus <i>Epinephelus</i> are nested within the <i>Mycteroperca</i> clade, indicating that these genera are not monophyletic. However, <i>E. malabaricus</i> remains within the <i>Epinephelus</i> clade. This study contributes to our comprehension of the taxonomy and genetic variation of <i>E. malabaricus</i> and underscores the importance of ongoing biodiversity monitoring in the region.</p>