Geometric Morphometric Analysis of Scale Shape for Discrimination of Lutjanidae and Serranidae from Bushehr Waters, Persian Gulf

Heydarnejad, Mohammad Saeed; Hashemi, Azar; Hashemzadeh Sagharloo, Iraj; Tabatabeee, Seydeh Narges

doi:10.22034/jmstsd.2026.579058.1005

Geometric Morphometric Analysis of Scale Shape for Discrimination of Lutjanidae and Serranidae from Bushehr Waters, Persian Gulf

Articles in Press

Document Type : Original Article

Authors

Mohammad Saeed Heydarnejad ¹

Azar Hashemi ²

Iraj Hashemzadeh sagharloo ²

seydeh narges tabatabeee ²

¹ Department of Zoology, Shahrekord University, POB 115

² 'بخش زیست شناسی- دانشگاه شهرکرذ Department of Biology,, Shahrekord University

10.22034/jmstsd.2026.579058.1005

Abstract

This study evaluated whether geometric morphometric analysis of fish scales can reliably discriminate between snappers (Lutjanidae, n=28) and groupers (Serranidae, n=40) from Bushehr waters, Persian Gulf. A total of 106 specimens were collected, but only specimens from these two families were analyzed (n=68). Six landmarks were digitized on scale images obtained from the operculum, dorsal fin region, and caudal peduncle using TPSdig2 software. Following Procrustes superimposition, data were analyzed with principal component analysis (PCA) and discriminant function analysis (DFA) using PAST software. Geometric shape analysis based on PCA and landmark configuration revealed that grouper scales are narrower, and the distal apex to the proximal base is oriented medially toward the landmark centroid. In contrast, snapper scales formed a cluster on the left side of the scatterplot of the first two principal components. Discriminant function analysis indicated that grouper and snapper scales could be separated with a resubstitution classification accuracy of 97% at the family level; however, this value was obtained without cross-validation and may therefore be overestimated. For the within-family analysis of snapper species, the first and secothe first disriminationnd principal components explained 70.98% and 12.25% of shape variation, respectively. Overall, these findings suggest that scale shape is a key feature for the identification of fish in this region

Keywords

Geometric morphometrics

scales

Grouper

Snapper

Persian Gulf

Subjects