Macro‐ and microscopic morphology of the flank scales of families Lutjanidae and Serranidae from the Persian Gulf Coral Reefs (Teleosts: Perciformes)

Abstract

Macro‐ and microscopic characteristics of flank scales for 12 species were investigated from the Persian Gulf Coral Reefs. In Lutjanus argentimaculatus and L. russellii (family Lutjanidae), the scales of different flank regions were not different, while four characters showed variation in the scale of L. lutjanus i.e., scale shape (pentagonal, hexagonal and square), anterior margin (waved, scalloped and smooth), focus shape (circular and oblong) and focus position (postero‐central and central), displayed variation. Scale type (ctenoid) and posterior margin (transforming ctenii) did not show variation and could be considered to be specific in this family. In Epinephelus chlorostigma (family Serranidae), the scales of flank regions did not display variation, while in E. areolatus, E. diacanthus and E. radiates, the scales showed considerable variation. The most variable characters were scale shape, posterior margin and focus shape. Therefore, in fish systematics studies on the base of scale, it is particularly important to compare scales from the same flank regions. Also, some criteria such as size‐dependent alternation, ontogenetic changes and variation between flank regions, should be considered. This study supports the potential of scale morphology to help for the understanding of fish diversity in the coral reef ecosystem.

Scale morphological variation across the flank in four Tonguefishes species collected from the Gulf of Oman (Pleuronectiforms; Cynoglossidae)

“…This work has attempted to account for the variations that occur in the examined Tonguefishes scales tofind characteristics that are constant/and vary over the flank and which might thus be used in the identification of the fish by the scale morphology. Previous studies have shown that the scale features change among different specimens, across the flank region and during the growth of individuals (Jawad, 2005;Sabbah et al, 2020;Teimori et al, 2021), but there are always distinct species-specific characteristics of the scales, which can be used for the taxonomic identification of fishes and also for reconstructions of phylogenetic and palaeogeographical relationships, (Gholami et al, 2013;Märss et al, 2006Märss et al, , 2007.…”