Landmark-Based Morphometric and Meristic Variations of Mola (Amblypharyngodon Mola) in Different Stocks of Ox-Bow Lake

Abstract

The present study was carried out in three different isolated ox-bow lakes of Baluhar, Marufdah, Joydia to analyse landmark-based morphometric measurements and meristic counts of a small indigenous species (SIS), Amblypharyngodon mola. A total of 90 samples were collected where the range of length was 47.83 to 73.63 mm and the weight range was 3.36–0.96 g. The main aim of this experiment was to evaluate the population status and to identify the variation among the stocks. Eleven morphometric characters and ten truss distances were measured. Nine morphometric characters namely pre-anal length (PAL), pre-pelvic length (PEL), pre-pectoral length (PEC), fork length (FL), maximum body height (MBH), lowest body height (LBH), head length (HL), eye diameter (ED) and pre-orbital length (POL) were found to be significantly different (p<0.05). Nine truss distances namely dst 1-2, dst 1-5, dst 1-6, dst 2-3, dst 2-5, dst 2-6, dst 3-6, dst 4-5 and dst 5-6 showed difference significantly (p<0.05). Conversely, standard length (SL), pre-dorsal length (PDL), dst 3-4 and any of meristic counts did not show significant difference among the stocks (p>0.05). The variation between the stocks occurred due to either environmental changes or genetic variation among the stocks. As meristic data did not show significant difference, environmental factors had more effect than genetical factors. This study is a preliminary step to identify the changes among the stocks of three ox-bow lakes, which can be a significant reference for formulating further management action plans.