Taxonomic Review of Genus Lutjanus (Perciformes Lutjanidae): Species Delimitation and Phylogenetic Insights

Abstract

Lutjanus comprises many economically and ecologically important reef-associated fishes in the family Lutjanidae and is commonly known as snappers. This review is the taxonomic synthesis of the genus, with an emphasis on the taxonomy, species richness, and key morphological, ecological, and genetic features. Lutjanus fishes inhabit warm coastal waters of tropical and subtropical zones, but their density is greatest in the Indo-Pacific region. The genus comprises more than 60 recognized species, but they display marked morphology, colouration, and ecological diversification patterns. This review focuses on the historical and contemporary perspectives of Lutjanus taxonomy. It presents morphological diagnostics, meristic counts, and molecular phylogenetics, all of which help to clarify the taxonomic challenges. More emphasis has been placed on assigning keys to identification difficulties stemming from phenotypic plasticity, hybridization, and cryptic speciation within the Genus. Furthermore, information about the biological functions, lifestyles, and ecological functions of Lutjanus species and their use in coral reefs and commercial recreationally are described. It also highlights the taxonomic knowledge voids that require investigations in future and directions for continuous improvements of integrative taxonomy to provide better insights for resolving phylogenetic relationships and species definitions.