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Our knowledge of the ability of coral reefs to face contemporary challenges disregards the wide variety of benthic communities (BCs) that could be associated with contrasted dynamics when facing stressors. Accordingly, this study investigates the number, characteristics, and distribution of BCs responsible for the development of coastal three‐dimensional structures in Taiwan. A total of 89 transects among three regions (north, east, and south) and two depths (−10 and −40 m) were characterized using a morpho‐functional categorization of benthic organisms. Using an unsupervised learning algorithm, k‐means cluster, an optimal number of k groups were identified among transects in order to minimize total intra‐group variance and represent a first level of organization, mirroring the number of BCs. Each BC was then described into prevailing categories and typified by an association with significant indicator groups. Their distributions were further examined and tested among regions and depths. Seven BCs were identified as having different composition and indicator categories. Their distributions suggest that, while sea surface temperature and light regime may be associated with a panel of available BCs, local conditions may have the final say on whether a BC eventually thrives at a given location. Overall, this study proposes an innovative and simple analytical framework for acknowledging differences among BCs. Our results encourage greater consideration of these shades in coral reef ecology studies, as they could conceal a variety of roles and dynamics important for the conservation of these endangered ecosystems.

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The richness of Taiwanese reef fish species is inversely correlated to latitude as a direct consequence of the abiotic environment and its effects on benthic habitats. However, to date, no studies have investigated the variations in the diversity of traits (FD) linked with the role of these fishes in the ecosystem. FD is usually considered more sensitive than species richness in detecting early changes in response to disturbances, and therefore could serve as an indicator of ecological resilience to environmental changes. Here, we aim to characterize FD in the Taiwanese reef fish fauna and to document its regional variations. Six traits were used to categorize the 1,484 reef fish species occurring in four environmentally contrasted regions around Taiwan. The number of unique trait combinations (FEs), their richness (FRic), their redundancy (FR), their over‐redundancy (FOR), and their vulnerability (FV) were compared among these regions. Overall, 416 FEs were identified. Their number decreased from south to north in step with regional species richness but FRic remained similar among regions. FR and FOR were higher to the south. At the local scale, variations in FEs and FRic are in concordance with the worldwide pattern of FD. High‐latitude, impoverished fish assemblages, offer a range of trait combinations similar to diversified tropical assemblages. Increasing diversity in the latter mainly contributes to raising FR and supports already over‐redundant entities. High vulnerability makes many combinations highly sensitive to species loss, and was higher at intermediate latitudes when using a fine resolution in trait categories. It suggests that the loss of FEs may first be characterized by an increase in their vulnerability, a pattern that could have been overlooked in previous global scale analyses. Overall, this study provides new insights into reef fish trait biogeography with potential ramifications for ecosystem functioning.