Research Article: Coincident use of fish taxonomy with sagitta and asteriscus otoliths to improve the identification of ponyfishes (Family: Leiognathidae)

Despite their small size, ponyfishes play a significant role in fisheries, both as catches and bycatches. However, their diversity remains poorly understood due to their similar appearances and limited knowledge. This study evaluates integrating body morphometrics with quantitative and morphological analysis of both sagittal and asteriscus otolith can provide reproducible diagnostic traits that resolve species-level ambiguities and clarify generic placement. Using discriminant function analysis (DFA) of truss network landmarks and otolith shape parameters, we examined ۵۵۶ specimens representing ۱۵ species from the northern Arabian Sea, including five new regional records. Furthermore, the statistical analysis of DFA revealed strong discriminatory power among genera, with the first four discriminant functions explaining ۶۲.۳%, ۱۱.۴%, ۸.۹%, and ۶.۱% of the variance (eigenvalues ۳۳.۸۵, ۶.۲۰, ۴.۸۴, and ۳.۲۹, respectively). Moreover, morphometrical study of otoliths showed the genera formed distinct clusters, and otolith characters provided consistent, complementary support: Aurigequula equula exhibited the largest sagittal otoliths (mean length ۶۹.۲۹ mm) with pronounced rostra (~۱۵.۵ mm) and deep notches (~۱۶.۶ mm), whereas members of Deveximentum had the smallest otoliths (۲.۵۱–۴.۱۵ mm) with markedly shorter rostra and shallower notches. Sagittal and asteriscus otoliths provided complementary diagnostic features, with asteriscus morphology offering novel resolution at species level. Collectively, these results indicate that three species from genus Leiognathus reassigned to their original generic placements under current nomenclatural standards. These findings demonstrate that otolith-based morphometrics, when combined with traditional taxonomy, can strengthen systematic frameworks, improve reproducibility in species identification, and contribute to ecological and evolutionary studies of Leiognathidae.

کلیدواژه ها:

Leiognathidae ، Discriminant function analysis ، Otolith morphology ، Species identification ، Northern Arabian Sea ، Taxonomy