Morphometric and meristic character variability and relationships among populations of Boops boops (L.) from four marine stations along the Tunisian coast

The variability of 14 morphometric and seven meristic characters of Boops boops (L.) collected at four stations along the Tunisian coast was examined in 518 samples ranging from 126 to 206 mm in total length and 37 to 78 g in total weight. Statistical analysis of both sets of characters showed significant variation among the four populations in 13 (92.9%) morphometric and four (57.1%) meristic characters. CVA and cluster analysis of the morphometric characters revealed four groups corresponding to four populations, with 95.36% correct classifications of individuals to their populations of origin. However, CVA and cluster analysis of the meristic characters showed a reticulate relationship among the four populations, as there was clear differentiation between those in Monastir and Zarzis and an overlap between those in Bizerte and Kelibia, with only 51.75% of individuals correctly classified to their respective populations. This morphological differentiation among the populations from the four stations was attributed to the differences in the physico-chemical water properties at these stations. However, further studies are needed on the impact of environmental factors and diet at these stations on the morphological population structure of B. boops to better understand the contribution of environmental conditions to morphological variation.